When GS method are used for retrieving wavefront, the results are not determinate. This paper reported our work of the uniqueness of phase in which GS method are used for retrieving wavefront of laser beam propagation through the turbulent atmosphere by using Numerical simulation, and put forward some new quadratic driving mends to GS method. Meanwhile, the results getting from GS method are given, and wavefront errors are also compared and analyzed. It is shown that the mends of GS method can not only resolve the uniqueness problems of GS method, but also quicken the speeds of the convergence.