diff --git a/packages/theme/system/index.less b/packages/theme/system/index.less
index 856cc354c..adc6c2523 100644
--- a/packages/theme/system/index.less
+++ b/packages/theme/system/index.less
@@ -1,5 +1,3 @@
-@import './theme-default.less';
-
 /** antd: base */
 @import 'ng-zorro-antd/style/entry.less';
 
diff --git a/packages/theme/system/theme-default.less b/packages/theme/system/theme-default.less
index 8fe309fc4..91492419e 100644
--- a/packages/theme/system/theme-default.less
+++ b/packages/theme/system/theme-default.less
@@ -1,6 +1,8 @@
 @import 'ng-zorro-antd/src/style/mixins/index.less';
 @import './mixins/index.less';
 
+@root-entry-name: default;
+
 // grey
 @grey-1:  #ffffff;
 @grey-2:  #fafafa;
diff --git a/packages/theme/system/theme-variable.less b/packages/theme/system/theme-variable.less
index 98a9abce3..ed473a3d4 100644
--- a/packages/theme/system/theme-variable.less
+++ b/packages/theme/system/theme-variable.less
@@ -1,5 +1,7 @@
 @import './theme-default.less';
 
+@root-entry-name: variable;
+
 @{html-selector} {
   --grey-1:  #fff;
   --grey-2:  #fafafa;