Abstract: The basic theory of a beam passing through the nonlinear medium is analysed in this paper, and the process of a tenstep high power supperGaussion beam passing through the nonlinear medium is calculated with the FFT. A negative nonlinear refractive index material was used as the compensating medium to compare different compensation methods. Studies suggest compensation can decrease B integral along the beam direction in a nonlinear medium, and can cancel the selffocusing of beams greatly. It can also avoid the nonlinear increase on the edges of superGaussian beams effectively. The compensation after nonlinear medium was selected as the idea compensating methods.