diff --git a/src/main/resources/templates/error/400.html b/src/main/resources/templates/error/400.html
index 3c7e32b..a9bf23d 100644
--- a/src/main/resources/templates/error/400.html
+++ b/src/main/resources/templates/error/400.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="zh-CN">
+<html lang="zh-CN" xmlns:th="http://www.thymeleaf.org">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1">
@@ -20,7 +20,7 @@
     <div class="code">400</div>
     <h1>请求参数有误</h1>
     <p>页面地址中的参数不正确（如页码格式错误）。<br>请修正后重试，或返回门户首页继续浏览。</p>
-    <a href="/cms/portal/">返回门户首页</a>
+    <a th:href="@{/portal/}" href="/portal/">返回门户首页</a>
 </div>
 </body>
 </html>
diff --git a/src/main/resources/templates/error/404.html b/src/main/resources/templates/error/404.html
index 83ad770..d25234c 100644
--- a/src/main/resources/templates/error/404.html
+++ b/src/main/resources/templates/error/404.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="zh-CN">
+<html lang="zh-CN" xmlns:th="http://www.thymeleaf.org">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1">
@@ -20,7 +20,7 @@
     <div class="code">404</div>
     <h1>页面不存在或已下线</h1>
     <p>您访问的页面可能已被删除、更改地址或暂时不可用。<br>请检查网址是否正确，或返回门户首页继续浏览。</p>
-    <a href="/cms/portal/">返回门户首页</a>
+    <a th:href="@{/portal/}" href="/portal/">返回门户首页</a>
 </div>
 </body>
 </html>
diff --git a/src/main/resources/templates/error/500.html b/src/main/resources/templates/error/500.html
index e2f6d75..ca5b598 100644
--- a/src/main/resources/templates/error/500.html
+++ b/src/main/resources/templates/error/500.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="zh-CN">
+<html lang="zh-CN" xmlns:th="http://www.thymeleaf.org">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1">
@@ -20,7 +20,7 @@
     <div class="code">500</div>
     <h1>服务暂时不可用</h1>
     <p>系统开小差了，工程师正在抢修。<br>请稍后刷新重试，或返回门户首页继续浏览。</p>
-    <a href="/cms/portal/">返回门户首页</a>
+    <a th:href="@{/portal/}" href="/portal/">返回门户首页</a>
 </div>
 </body>
 </html>
diff --git a/src/main/resources/templates/error/error.html b/src/main/resources/templates/error/error.html
index 976119f..6aeafb0 100644
--- a/src/main/resources/templates/error/error.html
+++ b/src/main/resources/templates/error/error.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="zh-CN">
+<html lang="zh-CN" xmlns:th="http://www.thymeleaf.org">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1">
@@ -20,7 +20,7 @@
     <div class="code">:(</div>
     <h1>出错了</h1>
     <p>请求处理出现异常，请稍后重试。<br>如持续出现，请联系管理员。</p>
-    <a href="/cms/portal/">返回门户首页</a>
+    <a th:href="@{/portal/}" href="/portal/">返回门户首页</a>
 </div>
 </body>
 </html>
diff --git a/src/test/java/com/yunhai/cms/portal/PortalErrorPageIT.java b/src/test/java/com/yunhai/cms/portal/PortalErrorPageIT.java
index 21d2794..3f401ea 100644
--- a/src/test/java/com/yunhai/cms/portal/PortalErrorPageIT.java
+++ b/src/test/java/com/yunhai/cms/portal/PortalErrorPageIT.java
@@ -60,6 +60,10 @@ class PortalErrorPageIT extends CmsIntegrationTestBase {
         assertThat(resp.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);
         assertThat(resp.getBody()).contains("页面不存在");
         assertThat(resp.getBody()).doesNotContain("\"status\":404");
+        // R-04：返回首页链接必须上下文感知（th:href="@{/portal/}"），不得硬编码 /cms 前缀
+        // （本测试无 context-path → 渲染为 /portal/；部署在 /cms 下则自动带 /cms）
+        assertThat(resp.getBody()).contains("href=\"/portal/\"");
+        assertThat(resp.getBody()).doesNotContain("/cms/portal/");
         assertThat(MediaType.parseMediaType(resp.getHeaders().getContentType().toString())
                 .includes(MediaType.TEXT_HTML)).isTrue();
     }