Abstract: Using Fourier model method, the near-field distribution of a total interual reflection(TIR) grating with high efficiency was analyzed under the irradiation of different polarized lights. The dependence of electric field enhancement in the TIR grating on constructive parameters and incident angle was also discussed. It is shown that electric field in the grating is sensitive to the polarization state, and peak electric field can be reduced greatly with short period and also decreases linearly with the increasing of incident angle. For the application of TIR grating to the high-energy laser system, reduction of the internal field enhancement can avoid the danger of damage effectively.