The action of channel storage was considered in the operation of flood control in river basin,the flood inverse routing method in river channel is a simplified method for joint operation of river and reservoir;Muskingum routing method is a conventional method for flood routing in river channel,but it can't be directly used for the flood inverse routing in river channel;so the process iteration method was provided in this paper,which combined Muskingum routing method and iterative trial-and-error method.The example showed that the method is practical and effective.