diff --git a/backend/tests/architecture-tests.js b/backend/tests/architecture-tests.js
index 8664f92..c2aef78 100644
--- a/backend/tests/architecture-tests.js
+++ b/backend/tests/architecture-tests.js
@@ -78,12 +78,17 @@ test('前端 package.json 与 lock 文件依赖同步且没有手工缓存版本
 test('生产部署统一使用 Vite dist 且不会删除 lock 文件', () => {
   const installer = fs.readFileSync(path.join(projectRoot, 'install.sh'), 'utf8');
   const nginxConfig = fs.readFileSync(path.join(projectRoot, 'nginx', 'nginx.conf'), 'utf8');
+  const nginxExample = fs.readFileSync(path.join(projectRoot, 'nginx', 'nginx.conf.example'), 'utf8');
   assert.ok(installer.includes('npm ci --include=dev'));
   assert.ok(installer.includes('npm run build'));
   assert.ok(installer.includes('frontend/dist'));
   assert.strictEqual(/rm\s+-rf\s+node_modules\s+package-lock\.json/.test(installer), false);
   assert.ok(nginxConfig.includes('root /usr/share/nginx/html;'));
   assert.ok(nginxConfig.includes('alias /runtime/downloads/;'));
+  for (const config of [installer, nginxConfig, nginxExample]) {
+    assert.ok(config.includes('proxy_hide_header X-Request-ID;'));
+    assert.ok(config.includes('proxy_hide_header Content-Security-Policy;'));
+  }
 });
 
 test('Docker 构建上下文排除依赖、环境配置和运行时数据', () => {
diff --git a/install.sh b/install.sh
index 624155b..933961f 100644
--- a/install.sh
+++ b/install.sh
@@ -2407,6 +2407,16 @@ server {
     add_header Permissions-Policy "camera=(), geolocation=(), microphone=()" always;
     add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'; img-src 'self' data: blob: https:; font-src 'self' data:; media-src 'self' blob: https:; connect-src 'self' https: ws: wss:; worker-src 'self' blob:; object-src 'none'; base-uri 'self'; frame-ancestors 'self'; form-action 'self';" always;
 
+    # 对外安全头由 Nginx 统一输出，避免与后端重复
+    proxy_hide_header X-Frame-Options;
+    proxy_hide_header X-Content-Type-Options;
+    proxy_hide_header X-XSS-Protection;
+    proxy_hide_header Referrer-Policy;
+    proxy_hide_header Permissions-Policy;
+    proxy_hide_header Strict-Transport-Security;
+    proxy_hide_header X-Request-ID;
+    proxy_hide_header Content-Security-Policy;
+
     # 隐藏Nginx版本号
     server_tokens off;
 
@@ -2707,6 +2717,16 @@ server {
     add_header Permissions-Policy "camera=(), geolocation=(), microphone=()" always;
     add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'; img-src 'self' data: blob: https:; font-src 'self' data:; media-src 'self' blob: https:; connect-src 'self' https: ws: wss:; worker-src 'self' blob:; object-src 'none'; base-uri 'self'; frame-ancestors 'self'; form-action 'self';" always;
 
+    # 对外安全头由 Nginx 统一输出，避免与后端重复
+    proxy_hide_header X-Frame-Options;
+    proxy_hide_header X-Content-Type-Options;
+    proxy_hide_header X-XSS-Protection;
+    proxy_hide_header Referrer-Policy;
+    proxy_hide_header Permissions-Policy;
+    proxy_hide_header Strict-Transport-Security;
+    proxy_hide_header X-Request-ID;
+    proxy_hide_header Content-Security-Policy;
+
     # 隐藏Nginx版本号
     server_tokens off;
 
@@ -2857,6 +2877,16 @@ server {
     add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'; img-src 'self' data: blob: https:; font-src 'self' data:; media-src 'self' blob: https:; connect-src 'self' https: ws: wss:; worker-src 'self' blob:; object-src 'none'; base-uri 'self'; frame-ancestors 'self'; form-action 'self';" always;
     add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
 
+    # 对外安全头由 Nginx 统一输出，避免与后端重复
+    proxy_hide_header X-Frame-Options;
+    proxy_hide_header X-Content-Type-Options;
+    proxy_hide_header X-XSS-Protection;
+    proxy_hide_header Referrer-Policy;
+    proxy_hide_header Permissions-Policy;
+    proxy_hide_header Strict-Transport-Security;
+    proxy_hide_header X-Request-ID;
+    proxy_hide_header Content-Security-Policy;
+
     # 隐藏Nginx版本号
     server_tokens off;
 
@@ -3621,6 +3651,35 @@ update_migrate_nginx_config() {
             mv "$secured_file" "$config_file"
         fi
 
+        if ! grep -q "proxy_hide_header X-Request-ID" "$config_file"; then
+            local proxy_headers_file="${config_file}.proxy-headers.$$"
+            if ! awk '
+                /add_header Content-Security-Policy/ && !inserted_proxy_headers {
+                    print
+                    print ""
+                    print "    # 对外安全头由 Nginx 统一输出，避免与后端重复"
+                    print "    proxy_hide_header X-Frame-Options;"
+                    print "    proxy_hide_header X-Content-Type-Options;"
+                    print "    proxy_hide_header X-XSS-Protection;"
+                    print "    proxy_hide_header Referrer-Policy;"
+                    print "    proxy_hide_header Permissions-Policy;"
+                    print "    proxy_hide_header Strict-Transport-Security;"
+                    print "    proxy_hide_header X-Request-ID;"
+                    print "    proxy_hide_header Content-Security-Policy;"
+                    inserted_proxy_headers = 1
+                    next
+                }
+                { print }
+                END { if (!inserted_proxy_headers) exit 2 }
+            ' "$config_file" > "$proxy_headers_file"; then
+                rm -f "$proxy_headers_file"
+                print_error "无法为 Nginx 配置添加上游响应头去重: $config_file"
+                cp -a "$backup_dir/$backup_name" "$config_file"
+                return 1
+            fi
+            mv "$proxy_headers_file" "$config_file"
+        fi
+
         if ! grep -q "location /downloads/" "$config_file"; then
             local migrated_file="${config_file}.migrate.$$"
             awk -v project_dir="$PROJECT_DIR" '
@@ -3638,7 +3697,9 @@ update_migrate_nginx_config() {
             mv "$migrated_file" "$config_file"
         fi
 
-        if ! grep -q "root ${PROJECT_DIR}/frontend/dist;" "$config_file" || ! grep -q "location /downloads/" "$config_file"; then
+        if ! grep -q "root ${PROJECT_DIR}/frontend/dist;" "$config_file" || \
+           ! grep -q "location /downloads/" "$config_file" || \
+           ! grep -q "proxy_hide_header X-Request-ID" "$config_file"; then
             print_error "无法安全迁移 Nginx 配置: $config_file"
             cp -a "$backup_dir/$backup_name" "$config_file"
             return 1
diff --git a/nginx/nginx.conf b/nginx/nginx.conf
index 79cf393..f9a822e 100644
--- a/nginx/nginx.conf
+++ b/nginx/nginx.conf
@@ -13,6 +13,16 @@ server {
     add_header Permissions-Policy "camera=(), geolocation=(), microphone=()" always;
     add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'; img-src 'self' data: blob: https:; font-src 'self' data:; media-src 'self' blob: https:; connect-src 'self' https: ws: wss:; worker-src 'self' blob:; object-src 'none'; base-uri 'self'; frame-ancestors 'self'; form-action 'self';" always;
 
+    # 对外安全头由 Nginx 统一输出，避免与后端重复
+    proxy_hide_header X-Frame-Options;
+    proxy_hide_header X-Content-Type-Options;
+    proxy_hide_header X-XSS-Protection;
+    proxy_hide_header Referrer-Policy;
+    proxy_hide_header Permissions-Policy;
+    proxy_hide_header Strict-Transport-Security;
+    proxy_hide_header X-Request-ID;
+    proxy_hide_header Content-Security-Policy;
+
     # 隐藏Nginx版本
     server_tokens off;
 
diff --git a/nginx/nginx.conf.example b/nginx/nginx.conf.example
index 0e9f432..d8320f1 100644
--- a/nginx/nginx.conf.example
+++ b/nginx/nginx.conf.example
@@ -52,6 +52,16 @@ server {
     add_header Permissions-Policy "camera=(), geolocation=(), microphone=()" always;
     add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'; img-src 'self' data: blob: https:; font-src 'self' data:; media-src 'self' blob: https:; connect-src 'self' https: ws: wss:; worker-src 'self' blob:; object-src 'none'; base-uri 'self'; frame-ancestors 'self'; form-action 'self';" always;
 
+    # 对外安全头由 Nginx 统一输出，避免与后端重复
+    proxy_hide_header X-Frame-Options;
+    proxy_hide_header X-Content-Type-Options;
+    proxy_hide_header X-XSS-Protection;
+    proxy_hide_header Referrer-Policy;
+    proxy_hide_header Permissions-Policy;
+    proxy_hide_header Strict-Transport-Security;
+    proxy_hide_header X-Request-ID;
+    proxy_hide_header Content-Security-Policy;
+
     # 隐藏 Nginx 版本
     server_tokens off;