diff --git a/app/controllers/announcements_controller.rb b/app/controllers/announcements_controller.rb
index 95615c58c6a..c1dbf079eb3 100644
--- a/app/controllers/announcements_controller.rb
+++ b/app/controllers/announcements_controller.rb
@@ -1,10 +1,17 @@
 # frozen_string_literal: true
 
 class AnnouncementsController < ApplicationController
+  PAGER_NUMBER = 25
   before_action :set_announcement, only: %i[show edit update destroy]
   before_action :rewrite_announcement, only: %i[update]
 
-  def index; end
+  def index
+    @announcements = Announcement.with_avatar
+                                 .preload(:comments)
+                                 .order(published_at: :desc, created_at: :desc)
+                                 .page(params[:page])
+                                 .per(PAGER_NUMBER)
+  end
 
   def show
     @announcements = Announcement.with_avatar.where(wip: false).order(published_at: :desc).limit(10)
@@ -14,23 +21,21 @@ def new
     @announcement = Announcement.new(target: 'students')
 
     if params[:id]
-      copy_announcement(params[:id])
+      @announcement = Announcement.copy_announcement(params[:id])
+      flash.now[:notice] = 'お知らせをコピーしました。'
     elsif params[:page_id]
       page = Page.find(params[:page_id])
-      copy_template_by_resource('page_announcements.yml', page:)
+      @announcement = Announcement.copy_template_by_resource('page_announcements.yml', page:)
     elsif params[:event_id]
       event = Event.find(params[:event_id])
-      copy_template_by_resource('event_announcements.yml', event:)
+      @announcement = Announcement.copy_template_by_resource('event_announcements.yml', event:)
     elsif params[:regular_event_id]
       regular_event = RegularEvent.find(params[:regular_event_id])
-      organizers = regular_event.organizers.map { |organizer| "@#{organizer.login_name}" }.join("\n    - ")
-      holding_cycles = ActiveDecorator::Decorator.instance.decorate(regular_event).holding_cycles
-      hold_national_holiday = "(祝日#{regular_event.hold_national_holiday ? 'も開催' : 'は休み'})"
-      copy_template_by_resource('regular_event_announcements.yml',
-                                regular_event:,
-                                organizers:,
-                                holding_cycles:,
-                                hold_national_holiday:)
+      params = { regular_event:,
+                 organizers: regular_event.organizers.map { |organizer| "@#{organizer.login_name}" }.join("\n    - "),
+                 holding_cycles: ActiveDecorator::Decorator.instance.decorate(regular_event).holding_cycles,
+                 hold_national_holiday: "(祝日#{regular_event.hold_national_holiday ? 'も開催' : 'は休み'})" }
+      @announcement = Announcement.copy_template_by_resource('regular_event_announcements.yml', params)
     end
   end
 
@@ -107,18 +112,4 @@ def set_entered_announcement
                                     description: params['announcement']['description'], \
                                     target: params['announcement']['target'])
   end
-
-  def copy_announcement(announcement_id)
-    announcement = Announcement.find(announcement_id)
-    @announcement.title       = announcement.title
-    @announcement.description = announcement.description
-    @announcement.target = announcement.target
-    flash.now[:notice] = 'お知らせをコピーしました。'
-  end
-
-  def copy_template_by_resource(template_file, params = {})
-    template = MessageTemplate.load(template_file, params:)
-    @announcement.title       = template['title']
-    @announcement.description = template['description']
-  end
 end
diff --git a/app/controllers/api/announcements_controller.rb b/app/controllers/api/announcements_controller.rb
deleted file mode 100644
index b1761fce3e7..00000000000
--- a/app/controllers/api/announcements_controller.rb
+++ /dev/null
@@ -1,53 +0,0 @@
-# frozen_string_literal: true
-
-class API::AnnouncementsController < API::BaseController
-  before_action :require_admin_login_for_api, only: %i[destroy]
-  before_action :set_announcement, only: %i[show update destroy]
-  protect_from_forgery except: %i[create update]
-
-  def index
-    @announcements = Announcement.with_avatar
-                                 .preload(:comments)
-                                 .order(published_at: :desc, created_at: :desc)
-                                 .page(params[:page])
-  end
-
-  def show; end
-
-  def update
-    # announcement_params['wip']はユーザーが入力をするので、(文字列で'false'入力した場合等)
-    # boolean型のtrueの時のみ「更新」が出来る様、明示的にtureを書き込んでいます。
-    if !current_user.admin? && announcement_params['wip'] != true
-      head :bad_request
-    elsif @announcement.update(announcement_params)
-      head :ok
-    else
-      head :bad_request
-    end
-  end
-
-  def create
-    @announcement = Announcement.new(announcement_params)
-    @announcement.user_id = current_user.id
-    @announcement.wip = true unless current_user.admin?
-    if @announcement.save
-      render :create, status: :created
-    else
-      head :bad_request
-    end
-  end
-
-  def destroy
-    @announcement.destroy
-  end
-
-  private
-
-  def announcement_params
-    params.fetch(:announcement).permit(:title, :description, :target, :wip)
-  end
-
-  def set_announcement
-    @announcement = Announcement.find(params[:id])
-  end
-end
diff --git a/app/javascript/components/announcement.vue b/app/javascript/components/announcement.vue
deleted file mode 100644
index 87850cd3a6d..00000000000
--- a/app/javascript/components/announcement.vue
+++ /dev/null
@@ -1,50 +0,0 @@
-<template lang="pug">
-.card-list-item(:class='announcement.wip ? "is-wip" : ""')
-  .card-list-item__inner
-    .card-list-item__user
-      a.card-list-item__user-link(:href='announcement.user.url')
-        span(:class='["a-user-role", roleClass]')
-          img.card-list-item__user-icon.a-user-icon(
-            :title='announcement.user.icon_title',
-            :alt='announcement.user.icon_title',
-            :src='announcement.user.avatar_url')
-    .card-list-item__rows
-      .card-list-item__row
-        .card-list-item-title
-          .a-list-item-badge.is-wip(v-if='announcement.wip')
-            span
-              | WIP
-          h2.card-list-item-title__title
-            a.card-list-item-title__link.a-text-link(:href='announcement.url')
-              | {{ announcement.title }}
-      .card-list-item__row
-        a.a-user-name(:href='announcement.user.url')
-          | {{ announcement.user.long_name }}
-      .card-list-item__row
-        .card-list-item-meta__items
-          .card-list-item-meta__item
-            .a-meta(v-if='announcement.wip')
-              | {{ title }}作成中
-            time.a-meta(v-else, datetime='announcement.published_at_date_time')
-              span.a-meta__label
-                | 公開
-              span.a-meta__value
-                | {{ announcement.published_at }}
-          .card-list-item-meta__item
-            .a-meta
-              | コメント（{{ announcement.commentsSize }}）
-</template>
-<script>
-export default {
-  props: {
-    title: { type: String, required: true },
-    announcement: { type: Object, required: true },
-    currentUser: { type: Object, required: true }
-  },
-  computed: {
-    roleClass() {
-      return `is-${this.announcement.user.primary_role}`
-    }
-  }
-}
-</script>
diff --git a/app/javascript/components/announcements.vue b/app/javascript/components/announcements.vue
deleted file mode 100644
index d4f52919790..00000000000
--- a/app/javascript/components/announcements.vue
+++ /dev/null
@@ -1,137 +0,0 @@
-<template lang="pug">
-.page-body
-  .container.is-md(v-if='!loaded')
-    loadingListPlaceholder
-  .container(v-else-if='announcements.length === 0')
-    .o-empty-message
-      .o-empty-message__icon
-        i.fa-regular.fa-smile
-      p.o-empty-message__text
-        | {{ title }}はありません
-  .container.is-md(v-else)
-    nav.pagination(v-if='totalPages > 1')
-      pager(v-bind='pagerProps')
-    .card-list.a-card
-      announcement(
-        v-for='announcement in announcements',
-        :key='announcement.id',
-        :title='title',
-        :announcement='announcement',
-        :currentUser='currentUser')
-    nav.pagination(v-if='totalPages > 1')
-      pager(v-bind='pagerProps')
-</template>
-
-<script>
-import CSRF from 'csrf'
-import LoadingListPlaceholder from 'loading-list-placeholder.vue'
-import Announcement from 'components/announcement.vue'
-import Pager from 'pager.vue'
-
-export default {
-  name: 'Announcements',
-  components: {
-    loadingListPlaceholder: LoadingListPlaceholder,
-    announcement: Announcement,
-    pager: Pager
-  },
-  props: {
-    title: { type: String, required: true },
-    currentUserId: { type: Number, required: true }
-  },
-  data() {
-    return {
-      announcements: [],
-      totalPages: 0,
-      currentPage: Number(this.getPageValueFromParameter()) || 1,
-      loaded: false,
-      currentUser: {}
-    }
-  },
-  computed: {
-    url() {
-      return `/api/announcements?page=${this.currentPage}`
-    },
-    pagerProps() {
-      return {
-        initialPageNumber: this.currentPage,
-        pageCount: this.totalPages,
-        pageRange: 5,
-        clickHandle: this.paginateClickCallback
-      }
-    }
-  },
-  created() {
-    window.onpopstate = function () {
-      location.replace(location.href)
-    }
-    this.getAnnouncementsPerPage()
-    this.getCurrentUser()
-  },
-  methods: {
-    getAnnouncementsPerPage() {
-      fetch(this.url, {
-        method: 'GET',
-        headers: {
-          'Content-Type': 'application/json; charset=utf-8',
-          'X-Requested-With': 'XMLHttpRequest',
-          'X-CSRF-Token': CSRF.getToken()
-        },
-        credentials: 'same-origin',
-        redirect: 'manual'
-      })
-        .then((response) => {
-          return response.json()
-        })
-        .then((json) => {
-          this.totalPages = json.total_pages
-          this.announcements = []
-          json.announcements.forEach((announcement) => {
-            this.announcements.push(announcement)
-          })
-          this.loaded = true
-        })
-        .catch((error) => {
-          console.warn(error)
-        })
-    },
-    getPageValueFromParameter() {
-      const url = location.href
-      const results = url.match(/\?page=(\d+)/)
-      if (!results) return null
-      return results[1]
-    },
-    paginateClickCallback(pageNumber) {
-      this.currentPage = pageNumber
-      this.getAnnouncementsPerPage()
-      history.pushState(
-        null,
-        null,
-        location.pathname + (pageNumber === 1 ? '' : `?page=${pageNumber}`)
-      )
-      window.scrollTo(0, 0)
-    },
-    getCurrentUser() {
-      fetch(`/api/users/${this.currentUserId}.json`, {
-        method: 'GET',
-        headers: {
-          'X-Requested-With': 'XMLHttpRequest'
-        },
-        credentials: 'same-origin',
-        redirect: 'manual'
-      })
-        .then((response) => {
-          return response.json()
-        })
-        .then((json) => {
-          for (const key in json) {
-            this.$set(this.currentUser, key, json[key])
-          }
-        })
-        .catch((error) => {
-          console.warn(error)
-        })
-    }
-  }
-}
-</script>
diff --git a/app/javascript/packs/application.js b/app/javascript/packs/application.js
index 9ee5b8eb3bf..9f15579527f 100644
--- a/app/javascript/packs/application.js
+++ b/app/javascript/packs/application.js
@@ -58,7 +58,6 @@ import '../editor-selection-form.js'
 import '../user_mentor_memo.js'
 
 import VueMounter from '../VueMounter.js'
-import Announcements from '../components/announcements.vue'
 import Books from '../components/books.vue'
 import ExternalEntries from '../components/external-entries.vue'
 import Questions from '../components/questions.vue'
@@ -78,7 +77,6 @@ import CourseBooks from '../components/course-books.vue'
 import '../stylesheets/application'
 
 const mounter = new VueMounter()
-mounter.addComponent(Announcements)
 mounter.addComponent(Books)
 mounter.addComponent(ExternalEntries)
 mounter.addComponent(Questions)
diff --git a/app/models/announcement.rb b/app/models/announcement.rb
index ba40f38e02f..c8dd0ebe188 100644
--- a/app/models/announcement.rb
+++ b/app/models/announcement.rb
@@ -25,4 +25,14 @@ class Announcement < ApplicationRecord
   columns_for_keyword_search :title, :description
 
   scope :wip, -> { where(wip: true) }
+
+  def self.copy_announcement(announcement_id)
+    original = find(announcement_id)
+    new(title: original.title, description: original.description, target: original.target)
+  end
+
+  def self.copy_template_by_resource(template_file, params = {})
+    template = MessageTemplate.load(template_file, params:)
+    new(title: template['title'], description: template['description'])
+  end
 end
diff --git a/app/views/announcements/_announcement.html.slim b/app/views/announcements/_announcement.html.slim
index f1e6ff576b8..e95aa467016 100644
--- a/app/views/announcements/_announcement.html.slim
+++ b/app/views/announcements/_announcement.html.slim
@@ -1,68 +1,34 @@
-.announcement.page-content
-  header.page-content-header
-    .page-content-header__start
-      .page-content-header__user
-        = render 'users/icon',
-          user: announcement.user,
-          link_class: 'page-content-header__user-link',
-          image_class: 'page-content-header__user-icon'
-    .page-content-header__end
-      .page-content-header__row
-        .page-content-header__before-title
-          time.a-meta(datetime="#{announcement.created_at.to_datetime}" pubdate='pubdate')
-            = l announcement.updated_at
-        h1.page-content-header__title(class="#{announcement.wip? ? 'is-wip' : ''}")
+.card-list-item
+  .card-list-item__inner
+    .card-list-item__user
+      = render 'users/icon', user: announcement.user, link_class: 'card-list-item__user-link', image_class: 'card-list-item__user-icon'
+    .card-list-item__rows
+      .card-list-item__row
+        header.card-list-item-title
           - if announcement.wip?
-            span.a-title-label.is-wip
+            span.a-list-item-badge.is-wip(class="#{announcement.wip? ? 'is-wip' : ''}")
               | WIP
-          = announcement.title
-      .page-content-header__row
-        .page-content-header-metas
-          .page-content-header-metas__start
-            .page-content-header-metas__meta
+          h2.card-list-item-title__title
+            = link_to announcement, itemprop: 'url', class: 'card-list-item-title__link a-text-link' do
+              = announcement.title
+      .card-list-item__row
+        .card-list-item-meta
+          .card-list-item-meta__items
+            .card-list-item-meta__item
               = link_to announcement.user, class: 'a-user-name' do
                 = announcement.user.long_name
-          .page-content-header-metas__end
-            .page-content-header-metas__meta
-              - length = @announcement.comments.length
-              a.a-meta(href='#comments' class="#{length.zero? ? 'is-disabled' : ''}")
-                | コメント（
-                span#comment_count(class="#{length.zero? ? 'is-muted' : 'is-emphasized'}")
-                  = length
-                | ）
-      .page-content-header__row
-        .page-content-header-actions
-          .page-content-header-actions__start
-            .page-content-header-actions__action
-              div(data-vue="WatchToggle" data-vue-watchable-id:number="#{@announcement.id}" data-vue-watchable-type='Announcement')
-          .page-content-header-actions__end
-            .page-content-header-actions__action
-              = link_to new_announcement_path(id: announcement), class: 'a-button is-sm is-secondary is-block', id: 'copy' do
-                i.fa-solid.fa-copy
-                | コピー
-
-  .a-card
-    .card-body
-      .card__description
-        .a-long-text.is-md.js-markdown-view
-          = announcement.description
-    hr.a-border-tint
-    = render 'reactions/reactions', reactionable: @announcement
-    hr.a-border-tint
-    .card-footer
-      .card-main-actions
-        ul.card-main-actions__items(class="#{announcement.published_at ? 'is-sub-actions' : ''}")
-          - if announcement.published_at
-            li.card-main-actions__item.is-sub
-              = link_to edit_announcement_path(announcement), class: 'card-main-actions__muted-action' do
-                | 内容修正
-          - else
-            li.card-main-actions__item
-              = link_to edit_announcement_path(announcement), class: 'card-main-actions__action a-button is-sm is-secondary is-block', id: 'js-shortcut-edit' do
-                i.fa-solid.fa-pen#new
-                | 内容修正
-          - if admin_or_mentor_login? || @announcement.user_id == current_user.id
-            li.card-main-actions__item.is-sub
-              = link_to announcement_path(announcement), data: { confirm: '本当によろしいですか？' }, method: :delete, class: 'card-main-actions__muted-action' do
-                span#delete
-                | 削除する
+      .card-list-item__row
+        .card-list-item-meta__items
+          .card-list-item-meta__item
+            - if announcement.wip?
+              .a-meta
+                | お知らせ作成中
+            - else
+              time.a-meta(datetime='announcement.published_at_date_time')
+                span.a-meta__label
+                  | 公開
+                span.a-meta__value
+                  | #{l announcement.published_at}
+          .card-list-item-meta__item
+            .a-meta
+              | コメント（#{announcement.comments.length}）
diff --git a/app/views/announcements/index.html.slim b/app/views/announcements/index.html.slim
index 4c2142c2050..315ed3b39f4 100644
--- a/app/views/announcements/index.html.slim
+++ b/app/views/announcements/index.html.slim
@@ -12,4 +12,17 @@ header.page-header
               i.fa-regular.fa-plus
               | お知らせ作成
 hr.a-border
-div(data-vue="Announcements" data-vue-title="#{title}" data-vue-current-user-id:number="#{current_user.id}")
+.page-body
+  - if @announcements.empty?
+    .container
+      .o-empty-message
+        .o-empty-message__icon
+          i.fa-regular.fa-smile
+        p.o-empty-message__text
+          | お知らせはありません
+  - else
+    .container.is-md
+      = paginate @announcements
+      .card-list.a-card
+        = render partial: 'announcement', collection: @announcements
+      = paginate @announcements
diff --git a/app/views/announcements/show.html.slim b/app/views/announcements/show.html.slim
index 1767bc2588d..4c3e74162c8 100644
--- a/app/views/announcements/show.html.slim
+++ b/app/views/announcements/show.html.slim
@@ -17,7 +17,74 @@ hr.a-border
 .page-body
   .page-body__inner.has-side-nav
     .container.is-md
-      = render 'announcement', announcement: @announcement
+      .announcement.page-content
+        header.page-content-header
+          .page-content-header__start
+            .page-content-header__user
+              = render 'users/icon',
+                user: @announcement.user,
+                link_class: 'page-content-header__user-link',
+                image_class: 'page-content-header__user-icon'
+          .page-content-header__end
+            .page-content-header__row
+              .page-content-header__before-title
+                time.a-meta(datetime="#{@announcement.created_at.to_datetime}" pubdate='pubdate')
+                  = l @announcement.updated_at
+              h1.page-content-header__title(class="#{@announcement.wip? ? 'is-wip' : ''}")
+                - if @announcement.wip?
+                  span.a-title-label.is-wip
+                    | WIP
+                = @announcement.title
+            .page-content-header__row
+              .page-content-header-metas
+                .page-content-header-metas__start
+                  .page-content-header-metas__meta
+                    = link_to @announcement.user, class: 'a-user-name' do
+                      = @announcement.user.long_name
+                .page-content-header-metas__end
+                  .page-content-header-metas__meta
+                    - length = @announcement.comments.length
+                    a.a-meta(href='#comments' class="#{length.zero? ? 'is-disabled' : ''}")
+                      | コメント（
+                      span#comment_count(class="#{length.zero? ? 'is-muted' : 'is-emphasized'}")
+                        = length
+                      | ）
+            .page-content-header__row
+              .page-content-header-actions
+                .page-content-header-actions__start
+                  .page-content-header-actions__action
+                    div(data-vue="WatchToggle" data-vue-watchable-id:number="#{@announcement.id}" data-vue-watchable-type='Announcement')
+                .page-content-header-actions__end
+                  .page-content-header-actions__action
+                    = link_to new_announcement_path(id: @announcement), class: 'a-button is-sm is-secondary is-block', id: 'copy' do
+                      i.fa-solid.fa-copy
+                      | コピー
+
+        .a-card
+          .card-body
+            .card__description
+              .a-long-text.is-md.js-markdown-view
+                = @announcement.description
+          hr.a-border-tint
+          = render 'reactions/reactions', reactionable: @announcement
+          hr.a-border-tint
+          .card-footer
+            .card-main-actions
+              ul.card-main-actions__items(class="#{@announcement.published_at ? 'is-sub-actions' : ''}")
+                - if @announcement.published_at
+                  li.card-main-actions__item.is-sub
+                    = link_to edit_announcement_path(@announcement), class: 'card-main-actions__muted-action' do
+                      | 内容修正
+                - else
+                  li.card-main-actions__item
+                    = link_to edit_announcement_path(@announcement), class: 'card-main-actions__action a-button is-sm is-secondary is-block', id: 'js-shortcut-edit' do
+                      i.fa-solid.fa-pen#new
+                      | 内容修正
+                - if admin_or_mentor_login? || @announcement.user_id == current_user.id
+                  li.card-main-actions__item.is-sub
+                    = link_to announcement_path(@announcement), data: { confirm: '本当によろしいですか？' }, method: :delete, class: 'card-main-actions__muted-action' do
+                      span#delete
+                      | 削除する
       #js-comments(data-commentable-id="#{@announcement.id}" data-commentable-type='Announcement' data-current-user-id="#{current_user.id}")
       div(data-vue='Footprints' data-vue-footprintable-id="#{@announcement.id}" data-vue-footprintable-type='Announcement')
     = render partial: 'recent_announcements'
diff --git a/app/views/api/announcements/_announcement.json.jbuilder b/app/views/api/announcements/_announcement.json.jbuilder
deleted file mode 100644
index cf57b7ac8de..00000000000
--- a/app/views/api/announcements/_announcement.json.jbuilder
+++ /dev/null
@@ -1,21 +0,0 @@
-json.id announcement.id
-json.user do
-  json.partial! "api/users/user", user: announcement.user
-end
-json.title announcement.title
-json.description announcement.description
-json.target announcement.target
-json.wip announcement.wip
-json.url announcement_path(id: announcement)
-json.new_url new_announcement_path(id: announcement)
-json.created_at l(announcement.created_at)
-json.created_at_date_time announcement.created_at.to_datetime
-json.updated_at l(announcement.updated_at)
-json.updated_at_date_time announcement.updated_at.to_datetime
-
-if announcement.published_at?
-  json.published_at l(announcement.published_at)
-  json.published_at_date_time announcement.published_at.to_datetime
-end
-
-json.commentsSize announcement.comments.size
diff --git a/app/views/api/announcements/create.json.jbuilder b/app/views/api/announcements/create.json.jbuilder
deleted file mode 100644
index cfaaad61c2d..00000000000
--- a/app/views/api/announcements/create.json.jbuilder
+++ /dev/null
@@ -1 +0,0 @@
-json.partial! "api/announcements/announcement", announcement: @announcement
diff --git a/app/views/api/announcements/index.json.jbuilder b/app/views/api/announcements/index.json.jbuilder
deleted file mode 100644
index 02b9666689c..00000000000
--- a/app/views/api/announcements/index.json.jbuilder
+++ /dev/null
@@ -1,6 +0,0 @@
-json.announcements do
-  json.array! @announcements do |announcement|
-    json.partial! "api/announcements/announcement", announcement: announcement
-  end
-end
-json.total_pages @announcements.page(1).total_pages
diff --git a/app/views/api/announcements/show.json.jbuilder b/app/views/api/announcements/show.json.jbuilder
deleted file mode 100644
index cfaaad61c2d..00000000000
--- a/app/views/api/announcements/show.json.jbuilder
+++ /dev/null
@@ -1 +0,0 @@
-json.partial! "api/announcements/announcement", announcement: @announcement
diff --git a/config/routes/api.rb b/config/routes/api.rb
index 9c184c69693..6a579e547e6 100644
--- a/config/routes/api.rb
+++ b/config/routes/api.rb
@@ -72,7 +72,6 @@
       resource :passed, only: %i(show), controller: 'passed'
     end
     resources :products, only: %i(index show)
-    resources :announcements, except: %i(new edit)
     resources :searchables, only: %i(index)
     resources :niconico_calendars, only: %i(show)
     resources :bookmarks, only: %i(index create destroy)
diff --git a/test/integration/api/announcements_test.rb b/test/integration/api/announcements_test.rb
deleted file mode 100644
index 3329a68545e..00000000000
--- a/test/integration/api/announcements_test.rb
+++ /dev/null
@@ -1,155 +0,0 @@
-# frozen_string_literal: true
-
-require 'test_helper'
-
-class API::AnnouncementsTest < ActionDispatch::IntegrationTest
-  fixtures :announcements
-
-  setup do
-    @announcement = announcements(:announcement1)
-    @my_announcement = announcements(:announcement4)
-  end
-
-  test 'GET /api/announcements.json' do
-    get api_announcements_path(format: :json)
-    assert_response :unauthorized
-
-    token = create_token('kimura', 'testtest')
-    get api_announcements_path(format: :json),
-        headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :ok
-  end
-
-  test 'POST /api/announcements.json' do
-    post api_announcements_path(format: :json),
-         params: {
-           announcement: {
-             title: 'test',
-             description: 'postのテストです'
-           }
-         }
-    assert_response :unauthorized
-
-    token = create_token('kimura', 'testtest')
-    post api_announcements_path(format: :json),
-         params: {
-           announcement: {
-             title: 'test',
-             description: 'postのテストです'
-           }
-         },
-         headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :created
-  end
-
-  test 'GET /api/announcements/1234.json' do
-    get api_announcement_path(@announcement.id, format: :json)
-    assert_response :unauthorized
-
-    token = create_token('kimura', 'testtest')
-    get api_announcement_path(@announcement.id, format: :json),
-        headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :ok
-  end
-
-  test 'PATCH /api/announcements/1234.json' do
-    patch api_announcement_path(@my_announcement.id, format: :json),
-          params: {
-            announcement: {
-              title: 'test',
-              description: 'patchのテストです'
-            }
-          }
-    assert_response :unauthorized
-
-    token = create_token('kimura', 'testtest')
-    patch api_announcement_path(@my_announcement.id, format: :json),
-          params: {
-            announcement: {
-              title: 'test',
-              description: 'patchのテストです'
-            }
-          },
-          headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :bad_request
-
-    token = create_token('komagata', 'testtest')
-    patch api_announcement_path(@my_announcement.id, format: :json),
-          params: {
-            announcement: {
-              title: 'test',
-              description: 'patchのテストです'
-            }
-          },
-          headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :ok
-  end
-
-  test 'DELETE /api/announcements/1234.json' do
-    delete api_announcement_path(@my_announcement.id, format: :json)
-    assert_response :unauthorized
-
-    token = create_token('kimura', 'testtest')
-    delete api_announcement_path(@announcement.id, format: :json),
-           headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :unauthorized
-
-    token = create_token('komagata', 'testtest')
-    delete api_announcement_path(@announcement.id, format: :json),
-           headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :no_content
-  end
-
-  test 'users except admin cannot publish an announcement when new' do
-    token = create_token('kimura', 'testtest')
-    post api_announcements_path(format: :json),
-         params: {
-           announcement: {
-             title: 'test',
-             description: 'postのテストです'
-           }
-         },
-         headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :created
-    assert Announcement.last.wip
-
-    token = create_token('komagata', 'testtest')
-    post api_announcements_path(format: :json),
-         params: {
-           announcement: {
-             title: 'test',
-             description: 'postのテストです',
-             wip: false
-           }
-         },
-         headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :created
-    assert_not Announcement.last.wip
-  end
-
-  test 'users except admin cannot publish an announcement when edit' do
-    token = create_token('kimura', 'testtest')
-    patch api_announcement_path(@my_announcement.id, format: :json),
-          params: {
-            announcement: {
-              title: 'test',
-              description: 'patchのテストです',
-              wip: false
-            }
-          },
-          headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :bad_request
-
-    token = create_token('komagata', 'testtest')
-    patch api_announcement_path(@my_announcement.id, format: :json),
-          params: {
-            announcement: {
-              title: 'test',
-              description: 'patchのテストです',
-              wip: false
-            }
-          },
-          headers: { 'Authorization' => "Bearer #{token}" }
-    assert_response :ok
-  end
-end
diff --git a/test/models/announcement_test.rb b/test/models/announcement_test.rb
new file mode 100644
index 00000000000..71925e3c335
--- /dev/null
+++ b/test/models/announcement_test.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+class AnnouncementTest < ActiveSupport::TestCase
+  test '.copy_announcement(announcement_id)' do
+    announcement = Announcement.create!(
+      user_id: users(:kimura).id,
+      title: 'お知らせのタイトルです',
+      description: 'お知らせの内容です',
+      target: 0
+    )
+    copied_announcement = Announcement.copy_announcement(announcement.id)
+
+    assert_equal copied_announcement.title, announcement.title
+    assert_equal copied_announcement.description, announcement.description
+    assert_equal copied_announcement.target, announcement.target
+  end
+
+  test '.copy_template_by_resource(template_file, params = {})' do
+    event = events(:event1)
+    template = MessageTemplate.load('event_announcements.yml', params: { event: })
+    announcement = Announcement.new(title: template['title'], description: template['description'])
+    announcement_based_template = Announcement.copy_template_by_resource('event_announcements.yml', event:)
+
+    assert_equal announcement_based_template.title, announcement.title
+    assert_equal announcement_based_template.description, announcement.description
+  end
+end
diff --git a/test/system/announcements_test.rb b/test/system/announcements_test.rb
index 4a30294bb78..21691e526e0 100644
--- a/test/system/announcements_test.rb
+++ b/test/system/announcements_test.rb
@@ -26,7 +26,7 @@ class AnnouncementsTest < ApplicationSystemTestCase
     user = users(:komagata)
     Announcement.delete_all
     26.times do
-      Announcement.create(title: 'test', description: 'test', user:)
+      Announcement.create(title: 'test', description: 'test', user:, published_at: DateTime.now)
     end
     visit_with_auth '/announcements', 'kimura'
     assert_selector 'nav.pagination', count: 2