The sloshing waves are analyzed using the displacement-based fluid finite element method.Two kinds of tanks are analyzed with one two dimensional rigid boundary conditions and the other 3D elastic boundary conditions.The sloshing frequency,free surface instantaneous elevation and time history of free surface elevation are obtained.The results of the rigid tank are found to be in good agreement with the linear analytical solutions,which verifies the feasibility of FE method.Free surface instantaneous elevation,time history of free surface elevation and the equivalent stresses in the elastic tank are obtained to give the influence of the sloshing waves on the tank.It mainly shows the advantage of the displacementbased fluid finite element method in dealing with the sloshing wave’s problem with elastic boundary condition.