diff --git a/front/src/api.ts b/front/src/api.ts
index c1557b9..58f6eaa 100644
--- a/front/src/api.ts
+++ b/front/src/api.ts
@@ -250,6 +250,17 @@ export interface PostCommentResponse {
 export const postComment = async (commentData: PostCommentRequest): Promise<PostCommentResponse> => {
   try {
     const identity = await get_id_token();
+    const hashtopic: string[] = [];
+    const regex = /#\S+/g;
+    const matches = commentData.content.match(regex);
+    if (matches) {
+      matches.forEach(tag => {
+        const cleanTag = tag.substring(1);
+        if (!hashtopic.includes(cleanTag)) {
+          hashtopic.push(cleanTag);
+        }
+      });
+    }
     const response = await fetch('/api/comment', {
       method: 'POST',
       headers: {
@@ -257,6 +268,7 @@ export const postComment = async (commentData: PostCommentRequest): Promise<Post
       },
       body: JSON.stringify({
         ...commentData,
+        hashtopic,
         identity,
       }),
     });
diff --git a/front/src/components/CommentSection.tsx b/front/src/components/CommentSection.tsx
index 9527f75..30897ec 100644
--- a/front/src/components/CommentSection.tsx
+++ b/front/src/components/CommentSection.tsx
@@ -16,6 +16,8 @@ import { Dismiss24Regular, ArrowReply24Regular } from '@fluentui/react-icons';
 import { getComments, postComment } from '../api';
 import type { Comment as CommentType } from '../api';
 import { useLayout } from '../context/LayoutContext';
+import ReactMarkdown from 'react-markdown';
+import remarkGfm from 'remark-gfm';
 
 const useStyles = makeStyles({
   container: {
@@ -85,8 +87,43 @@ const useStyles = makeStyles({
     height: '40px',
     fontSize: '16px',
   },
+  tag: {
+    color: tokens.colorBrandForeground1,
+    textDecoration: 'none',
+  },
 });
 
+// 自定义 remark 插件，用于高亮 #tag
+const remarkTagPlugin = () => {
+  return (tree: any) => {
+    const transformNode = (node: any, inLink = false) => {
+      if (node.type === 'link') inLink = true;
+
+      if (node.children) {
+        node.children = node.children.flatMap((child: any) => {
+          if (child.type === 'text' && !inLink) {
+            const parts = child.value.split(/(#\S+)/g);
+            return parts.map((part: string) => {
+              if (part.match(/^#\S+$/)) {
+                return {
+                  type: 'link',
+                  url: 'tag:' + part,
+                  children: [{ type: 'text', value: part }]
+                };
+              }
+              if (part === "") return [];
+              return { type: 'text', value: part };
+            }).flat();
+          }
+          return transformNode(child, inLink);
+        });
+      }
+      return node;
+    };
+    transformNode(tree);
+  };
+};
+
 interface CommentSectionProps {
   postId: number;
 }
@@ -188,7 +225,21 @@ const CommentSection: React.FC<CommentSectionProps> = ({ postId }) => {
             <div className={styles.commentHeader}>
               <Text className={styles.nickname}>{comment.nickname}</Text>
             </div>
-            <Text>{comment.content}</Text>
+            <div style={{ whiteSpace: 'pre-wrap' }}>
+              <ReactMarkdown
+                remarkPlugins={[remarkGfm, remarkTagPlugin]}
+                components={{
+                  a: ({ node, ...props }) => {
+                    if (props.href && props.href.startsWith('tag:')) {
+                      return <span className={styles.tag}>{props.children}</span>;
+                    }
+                    return <a {...props} />;
+                  },
+                }}
+              >
+                {comment.content}
+              </ReactMarkdown>
+            </div>
             <div className={styles.commentFooter}>
               <Tooltip content="回复" relationship="label">
                 <div