Abstract: Computational model of progressive failure in composite sandwich structures is built up to predict the face fracture,delamination failure and core failure. Nonlinear geometry equations and energy variational equation is estimated according to overall bulking of composite sandwich plates. The nonlinear stability governing equations of anti-symmetrical buckling of sandwich plate are deduced, considering the transverse shear deformation influence of core. In order to solve the governing equations, the method of generalized double Fourier series is employed. Tsai-Wu failure criteria and Maximum stress criteria are proposed to predict composite face-sheet failure,core failure and interlaminar failure. These failure criteria and stiffness reduction are used to obtain critical load,post-bulking behavior and limit load.