diff --git a/server-rs/crates/api-server/src/request_context.rs b/server-rs/crates/api-server/src/request_context.rs
index 9cd65b410..9a1f58743 100644
--- a/server-rs/crates/api-server/src/request_context.rs
+++ b/server-rs/crates/api-server/src/request_context.rs
@@ -107,19 +107,22 @@ pub async fn attach_request_context(mut request: Request, next: Next) -> Respons
         .await
 }
 
-/// 从代理头解析客户端 IP：反代固定用 `x-forwarded-for` 的第一个地址，直连（本地开发）
-/// 回退 `x-real-ip`，都拿不到时才兜底回环地址。
+/// 从代理头解析客户端 IP。
+///
+/// 优先 `x-real-ip`：nginx 用 `$remote_addr` 覆盖写入，是真实 TCP 对端，调用方无法伪造。
+/// `x-forwarded-for` 只作回退，并取**最后一段**——nginx 用 `$proxy_add_x_forwarded_for` 会把真实
+/// 对端追加在末尾，前面几段是调用方自带的、可伪造。两者都拿不到时才兜底回环地址。
 pub fn client_ip_from_headers(headers: &HeaderMap) -> String {
     headers
-        .get("x-forwarded-for")
+        .get("x-real-ip")
         .and_then(|value| value.to_str().ok())
-        .and_then(|value| value.split(',').next())
         .map(str::trim)
         .filter(|value| !value.is_empty())
         .or_else(|| {
             headers
-                .get("x-real-ip")
+                .get("x-forwarded-for")
                 .and_then(|value| value.to_str().ok())
+                .and_then(|value| value.rsplit(',').next())
                 .map(str::trim)
                 .filter(|value| !value.is_empty())
         })
@@ -170,20 +173,33 @@ mod tests {
     }
 
     #[test]
-    fn client_ip_prefers_first_forwarded_address() {
+    fn client_ip_prefers_real_ip_over_forwarded_for() {
         let mut headers = HeaderMap::new();
         headers.insert(
             "x-forwarded-for",
             HeaderValue::from_static("203.0.113.7, 10.0.0.1"),
         );
-        assert_eq!(client_ip_from_headers(&headers), "203.0.113.7");
+        headers.insert("x-real-ip", HeaderValue::from_static("198.51.100.9"));
+        assert_eq!(client_ip_from_headers(&headers), "198.51.100.9");
     }
 
     #[test]
-    fn client_ip_falls_back_to_real_ip_then_loopback() {
+    fn client_ip_forwarded_for_fallback_uses_last_address() {
+        // nginx 把真实对端追加在末尾，前面是调用方可伪造的值，只能取最后一段。
         let mut headers = HeaderMap::new();
-        headers.insert("x-real-ip", HeaderValue::from_static("198.51.100.9"));
-        assert_eq!(client_ip_from_headers(&headers), "198.51.100.9");
+        headers.insert(
+            "x-forwarded-for",
+            HeaderValue::from_static("203.0.113.7, 10.0.0.1"),
+        );
+        assert_eq!(client_ip_from_headers(&headers), "10.0.0.1");
+    }
+
+    #[test]
+    fn client_ip_ignores_blank_real_ip_and_falls_back_then_loopback() {
+        let mut headers = HeaderMap::new();
+        headers.insert("x-real-ip", HeaderValue::from_static("   "));
+        headers.insert("x-forwarded-for", HeaderValue::from_static("10.0.0.1"));
+        assert_eq!(client_ip_from_headers(&headers), "10.0.0.1");
         assert_eq!(client_ip_from_headers(&HeaderMap::new()), "127.0.0.1");
     }
 }