diff --git a/modules/api.js b/modules/api.js
index 0ece71e..962f776 100644
--- a/modules/api.js
+++ b/modules/api.js
@@ -72,7 +72,7 @@ app.post('/api/sign_up', async (req, res) => {
     user = await User.findOne({ where: { email: req.body.email } });
     if (user) throw 2009;
 
-    if (!req.body.nickname) {
+    if (!req.body.nickname.trim()) {
       res.send({
         error_code: 2300,
         message : "昵称不能为空"
diff --git a/views/ranklist.ejs b/views/ranklist.ejs
index 1fd1afa..d461995 100644
--- a/views/ranklist.ejs
+++ b/views/ranklist.ejs
@@ -39,7 +39,7 @@
             %>
             <tr>
 		        	<td><b><%= i %></b></td>
-		        	<td><a href="<%= syzoj.utils.makeUrl(['user', user.id]) %>"><%= user.nickname %></a><% if (user.nameplate) { %><%- user.nameplate %><% } %></td>
+		        	<td><a href="<%= syzoj.utils.makeUrl(['user', user.id]) %>"><% if(!user.nickname || user.nickname.trim() === '') { %> <%= user.username %> <% } else { %> <%= user.nickname %> <% } %></a><% if (user.nameplate) { %><%- user.nameplate %><% } %></td>
 		        	<td><%= user.ac_num %></td>
               <td><%= user.submit_num %></td>
               <td><%= user.ac_num && user.submit_num ? Math.round(user.ac_num / user.submit_num * 10000) / 100.00 + "%" : 0%></td>