The higher-order shear deformation theory, which has the parabolic distribution of the transverse shear strains through the thickness of the plate and for zero transverse shear stresses on the plate surface, was employed for the buckling analysis of asymmetrical angle-ply laminates subjected to shear loading. It should be pointed out that the pb-2 Ritz functions, which consist of the product of a basic function and a two dimensional polynomial function, was introduced to represent an arbitrary edge condition, and thus the proposed analysis could obviate the tedious task of searching the displacement function to meet various edge supports. It was found that the buckling load in general asymmetrical laminates under normal shear loading was quite different from that under inverse shear loading, while there was not difference in anti-symmetric laminates. Furthermore, According to the analysis, the effect of boundary conditions, aspect ratios of the plate, lamination angle and the modulus of elasticity on buckling load and buckling mode were made clear. It was shown that the present method could be used to analyze the buckling behavior of almost laminated composite plates.