In order to analyse the mechanical characteristics of single anchor sheet pile structure in Xinxiagang double-lane lock,we establish the finite mesh model with ABAQUS.We discusse the choice of soil constitutive model during the excavation of chamber after contruction process has been taken into consideration.At the same time,we get the distribution of deformation and bending moment and the variaty of earth pressure before and after the sheet pile by analyzing the force characteristics of single anchor sheet pile structure during the construction and using period.The results show that for deep excavation problem,modified Cam-Clay model can reflect the bulk properties of soil better and when the construction is completed the earth pressure behind the piles performs the classic “R” type distribution while the earth pressure before the pile is basically a straight line,but in the face of the excavation,the stress will increase substantially due to the deformation and squeeze of sheet pile.During the using period of the lock,water level changes frequently and the floor brace can bear about 80% of the pressure increment caused by the water pressure.That means it can effectively improve the stress state of the sheet pile structure.