In view of the excessive speed of cross-flow in entrance area of the approach channel of ship lock reconstruction in Jiepai junction project, we adjust the length of water diversion wall and the elevation of hanging plate, apply flow condition test to obtain a reasonable and feasible general layout optimization scheme of approach channel.Aiming at the problem that the geological condition of the downstream approach channel changes and the mixed structure used in the original design is no longer applicable, we carry out the economic and technological comparison between the gravity structure and the gravity pier+hanging plate structure, and determine the changed scheme.The results show that the gravity structure has strong anti ship impact ability, simple construction and slightly higher investment, which can be used as the recommended scheme.