diff --git a/lib.go b/lib.go
index bb66a61..34ef38d 100644
--- a/lib.go
+++ b/lib.go
@@ -54,7 +54,11 @@ func (c *Cli) Do(method string, strurl string, body []byte) (*http.Response, err
 			req.Header.Set(k, v)
 		}
 	}
-	return c.cli.Do(req)
+	res,err:= c.cli.Do(req)
+	if err==nil && res.StatusCode >=400{
+		return nil, errors.New("Http return code - %d: %s",res.StatusCode,res.Status)
+	}
+	return res,err
 }
 func (c *Cli) DoJson(method string, strurl string, i interface{}, o interface{}) (err error) {
 	bs, err := json.Marshal(i)