diff --git a/models/article.js b/models/article.js
index ca510ad..977a6ed 100644
--- a/models/article.js
+++ b/models/article.js
@@ -91,6 +91,19 @@ class Article extends Model {
     return user && (this.allow_comment || user.is_admin || this.user_id === user.id);
   }
 
+  async resetReplyCountAndTime() {
+    let ArticleComment = syzoj.model('article-comment');
+    await syzoj.utils.lock(['Article::resetReplyCountAndTime', this.id], async () => {
+      this.comments_num = await ArticleComment.count({ article_id: this.id });
+      if (this.comments_num === 0) {
+        this.sort_time = this.public_time;
+      } else {
+        this.sort_time = await ArticleComment.model.max('public_time', { where: { article_id: this.id } });
+      }
+      await this.save();
+    });
+  }
+
   getModel() { return model; }
 };
 
diff --git a/modules/admin.js b/modules/admin.js
index e68228b..72673b9 100644
--- a/modules/admin.js
+++ b/modules/admin.js
@@ -320,6 +320,11 @@ app.post('/admin/other', async (req, res) => {
       for (const p of problems) {
         await p.resetSubmissionCount();
       }
+    } else if (req.body.type === 'reset_discussion') {
+      const articles = await Article.query();
+      for (const a of articles) {
+        await a.resetReplyCountAndTime();
+      }
     } else {
       throw new ErrorMessage("操作类型不正确");
     }
diff --git a/views/admin_other.ejs b/views/admin_other.ejs
index ee5a8dd..d0b1ef6 100644
--- a/views/admin_other.ejs
+++ b/views/admin_other.ejs
@@ -1,7 +1,8 @@
 <% this.adminPage = 'other'; %>
 <% include admin_header %>
 <form method="post" class="ui form">
-  <button class="ui blue button" name="type" value="reset_count" type="submit">重新计算提交及 AC 数</button>
+  <p><button class="ui blue button" name="type" value="reset_count" type="submit">重新计算提交及 AC 数</button></p>
+  <p><button class="ui blue button" name="type" value="reset_discussion" type="submit">重新计算讨论版回复数和回复时间</button></p>
   <!-- <button name="type" value="reset_size" type="submit">重新计算代码大小</button> -->
 </form>
 <% include admin_footer %>