diff --git a/404.html b/404.html
new file mode 100644
index 0000000..620b0e0
--- /dev/null
+++ b/404.html
@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <link rel="shortcut icon" href="/img/title.jpg">
+    <title>404 Not Found</title>
+</head>
+<body>
+    <div style="width: 75%; margin: auto;">
+        <h1>呀！文件失踪了！</h1>
+        <p>对不起，我们找不到链接指向的文件。如果你是从外部网站链接来的，请告诉那个网站的管理员。</p>
+        <br>
+    <a href="https://ajjdxns.github.io">返回主页</a> 或 <a href="https://github.com/ajjdxns/ajjdxns.github.io/issues">将这个错误告诉我们</a>
+    </div>
+</body>
+</html>
\ No newline at end of file
