diff --git a/src/server/startup.rs b/src/server/startup.rs
index 8a0e5db..3a1ebee 100644
--- a/src/server/startup.rs
+++ b/src/server/startup.rs
@@ -160,11 +160,16 @@ async fn start_grpc_server(config: &ServerConfig, app_state: Arc<AppState>) -> R
     let server = Server::builder()
         // Timeout configurations
         .timeout(Duration::from_secs(60)) // 60 seconds timeout for gRPC requests
-        .http2_keepalive_interval(Some(Duration::from_secs(30)))
-        .http2_keepalive_timeout(Some(Duration::from_secs(90)))
-        .tcp_keepalive(Some(Duration::from_secs(60)))
+        // HTTP/2 Keepalive settings - 강화된 설정
+        .http2_keepalive_interval(Some(Duration::from_secs(10))) // 10초마다 ping
+        .http2_keepalive_timeout(Some(Duration::from_secs(20))) // 20초 응답 대기
+        .http2_adaptive_window(Some(true)) // 적응형 윈도우 크기
+        // TCP Keepalive
+        .tcp_keepalive(Some(Duration::from_secs(20))) // TCP keepalive 20초
         // Performance optimizations
         .max_concurrent_streams(Some(config.max_concurrent_requests as u32))
+        .initial_stream_window_size(Some(1024 * 1024)) // 1MB 스트림 윈도우
+        .initial_connection_window_size(Some(2 * 1024 * 1024)) // 2MB 연결 윈도우
         .tcp_nodelay(true)
         // Note: accept_http1 removed to allow ELB health checks
         .add_service(sync_service)