diff --git a/httpclient/client.go b/httpclient/client.go
index c798a39..6abab1b 100644
--- a/httpclient/client.go
+++ b/httpclient/client.go
@@ -75,6 +75,12 @@ func NewHttpClient(reqConfig *define.Request, cacheInstance cache.ICache) (*Http
 			}
 		}
 	}
+	if reqConfig.Header == nil {
+		reqConfig.Header = make(map[string]any)
+	}
+	if ua, exist := reqConfig.Header[consts.HeaderKeyUserAgent.String()]; !exist || nil == ua || fmt.Sprintf("%v", ua) == "" {
+		reqConfig.Header[consts.HeaderKeyUserAgent.String()] = "resty-v2@network/httpclient"
+	}
 	restyClient, restyRequest := NewRestyClient(reqConfig)
 	hc := &HttpClient{
 		Client:                   restyClient,