The calculation method of stiffened composite panel buckling load varies with different load conditions. Considering different thick equivalence of hat-stiffened stringer foot for the skin, the applicability of several engineering calculation methods for buckling load of hat-stiffened composite panel with four edges simply supported and fixed supported subjected to axial compression was investigated, and calculation results were compared with experimental data in this paper. The results show that the method which considers four edges simply supported and provided, and the axial stiffness of stringer and skin were the same matches favorably well with experimental data and the error is within the tolerance scope. Since there are large number of the test panels, the test panel structure, stacking sequence of the laminate as well as the boundary conditions express typical, and representative characters, and pertinence with certain engineering structure. The calculation method has good reference for aircraft program design and quick strength analysis.