diff --git a/vnpy/api/okexfuture/OkexFutureApi.py b/vnpy/api/okexfuture/OkexFutureApi.py
index 507ae2c2..9d9809e8 100644
--- a/vnpy/api/okexfuture/OkexFutureApi.py
+++ b/vnpy/api/okexfuture/OkexFutureApi.py
@@ -142,7 +142,7 @@ class OkexFutureRestClient(OkexFutureRestBase):
     def sendOrder(self, symbol, contractType, orderType, volume,
                   onSuccess, onFailed=None,
                   price=None, useMarketPrice=False, leverRate=None,
-                  extra=None):  # type:(str, OkexFutureContractType, OkexFutureOrderType, float, Callable[[int, Any], Any], Callable[[int, Any], Any], float, bool, Union[int, None], Any)->Request
+                  extra=None):  # type:(str, OkexFutureContractType, OkexFutureOrderType, float, Callable[[str, Any], Any], Callable[[int, Any], Any], float, bool, Union[int, None], Any)->Request
         """
         :param symbol: str
         :param contractType: OkexFutureContractType