diff --git a/swoole_client.cc b/swoole_client.cc
index d68819bc213..fed22f27139 100644
--- a/swoole_client.cc
+++ b/swoole_client.cc
@@ -415,7 +415,7 @@ void php_swoole_client_check_setting(swClient *cli, zval *zset)
     {
         cli->open_length_check = zval_is_true(ztmp);
         cli->protocol.package_length_size = SW_MQTT_MIN_LENGTH;
-        cli->protocol.package_length_offset = 0;
+        cli->protocol.package_length_offset = 1;
         cli->protocol.package_body_offset = 0;
         cli->protocol.get_package_length = swMqtt_get_package_length;
     }
diff --git a/swoole_socket_coro.cc b/swoole_socket_coro.cc
index 099ac39c6ea..d3b954008da 100644
--- a/swoole_socket_coro.cc
+++ b/swoole_socket_coro.cc
@@ -953,7 +953,7 @@ SW_API bool php_swoole_socket_set_protocol(Socket *sock, zval *zset)
     {
         sock->open_length_check = zval_is_true(ztmp);
         sock->protocol.package_length_size = SW_MQTT_MIN_LENGTH;
-        sock->protocol.package_length_offset = 0;
+        sock->protocol.package_length_offset = 1;
         sock->protocol.package_body_offset = 0;
         sock->protocol.get_package_length = swMqtt_get_package_length;
     }