Abstract: The buckling analysis of symmetrically laminated composite plates loaded in compression and shear is presented by using the pb-2 Ritz functions, which consist of the product of a basic function and a two dimensional polynomial function. The outplane shear deformation is also taken into consideration in this analysis. It is shown that the convergence of solutions for the buckling load is good when the number of polynomials is more than 20. Numerical results are obtained for symmetrical angle-ply laminated composite plates. The effects of material properties, plate aspect ratio, number of layers and lamination angle on buckling load are also investigated under simple supported, clamped edges and combined edge conditions. It is shown that the presented method considering the outofplane shear deformation can be widely used to analyze the buckling behavior of composite plates with general boundary conditions.