Based on second line ship lock of Mengtze junction in Beijiang River of Guangdong Province,to solve the problems of backfilling,large amount of excavation and large internal force of ground wall cofferdam construction platform,a new type of wall cofferdam structure is proposed and adopted in the lower part of the wall and upper retaining wall,which effectively reduces the backfill,excavation and internal force of the construction platform.Using conventional monolithic or separate lock head makes,the amount of excavation and concrete is large,and water seal is complicated and poor reliability .In order to solve this problem,a new type of integral gate head structure is proposed and adopted,through which water seal is simple and reliable,and effectively reduces the amount of excavation and the amount of concrete used.As the low construction accuracy of piles inserted plate wall,it’ s difficult to guarantee the flapper can be installed successfully.Adopting the idea of active-compensation,steel sleeve was set outside the steel casing,and reasonable gaps were reserved. A new type of piles inserted plate wall was used to ensure the success installation of flapper.