Water diversion project from the Yangtze River to the Huaihe River is a major strategic allocation of water resources engineering,which has tasks such as water supply,navigation,ecology and other development. It is planned to choose Zongyang hub as the diversion channel,and a 1000-ton ship lock is to be constructed,acting as a channel connected with the Yangtze River main waterway. By checking channel conditions of Zhongyang branch，we use the mathematical model to analyze the flow pattern of the lock’s outlet.It is concluded that the Zhongyang branch can be used as a route.Through the design ship,channel width,depth and bend radius,we propose a reasonable shipping line plan.