In response to the problems of water facing all sides of the Dongfeihe River lock from the Yangtze River to Huaihe River,complex construction conditions,and one-time formation of the lock chamber wall,this paper analyzes hydrological and geological conditions,and conducts a comparative test of the dewatering well to determine the deep foundation pit dewatering plan and monitoring method.Based on the existing installation methods of steel bar for lock chamber wall and miter gate,this paper analyzes the existing problems,and puts forward some construction techniques,such as integral prefabrication and installation of steel bar for lock chamber wall,fine fabrication and precise positioning of miter gate.The research results made the construction of Dongfei River double line ship lock successfully and improved the safety and quality of ship lock construction.The application of the steel prefabrication technology in the lock chamber wall project further enriches and improves the construction methods and quality of the reconstruction and expansion of ship lock.