Liquid crystal spatial light modulator (LC-SLM) is a perfect wavefront generato r.As a dynamic diffractive device,it has some advantages such as high resolution ,low cost,small-size pixels and real-time programming. For a reflecting LC-SLM,the curvature error of its reflective substrate and the fringe field effect of liquid crystal cell can reduce the wavefront generation precision to limit the device′s application in wavefront control field.We research the wavefront generation method using liqui d crystal spatial light modulator. In order to find an effective method to improve the wavefront generation precisi on,the static-error compensation and residual-error feedback methods are proposed.The experimental results show that liquid crystal spatial light modulator can give good performance on generating eight wavefront aberations including defocus, astigmatism,coma and spherical aberration based on Zernike polynomials.But the RMS of generation errors is averagely 0.265λ.The RMS of gen eration errors respectively reduces by 0.223λ and 0.170λ by using static-error compensation and residual-error feedback methods,and abviously the latter metho d is more effective.Improving the wavefront generation precision can make LC-SLM h ave wide application in adaptive optic,femtosecond laser processing,real-time holography display and optical m easurement fields.