diff --git a/lib/markdown.ts b/lib/markdown.ts
index f9ce4d675..86725a77e 100644
--- a/lib/markdown.ts
+++ b/lib/markdown.ts
@@ -26,6 +26,9 @@ import siteConfig from "@/config/siteConfig";
  * @returns: { mdxSource: mdxSource, frontMatter: ...}
  */
 const parse = async function (source, format, scope) {
+  if (siteConfig.preProcess) {
+    source = siteConfig.preProcess(source);
+  }
   const { content, data } = matter(source);
   const permalinks = await getPermalinks(siteConfig.content);