Abstract: To analyze composite hat-stiffened panels, several calculation methods were adopted firstly for calculating the compression buckling performance of composite hat-stiffened panels under axial compression to obtain the buckling load under two boundary conditions and three widths of sample. The buckling loads of different calculation methods were obtained. The calculation results were compared with the test results in order to find out a simple and effective method of obtaining buckling load of hat-stiffened composite panels under axial compression. According to dense stiffener in hat-stiffened panel of current aircraft structure, the structure characters and failure patterns of hat-stiffened composite panels, a simple calculation method was proposed to estimate the failure loads of hat-stiffened composite panels under axial compression. Calculation results accord with the test results well, which validates the rationality of engineering method. It is preferable accuracy to estimate the failure load of composite hat-stiffened panels by the engineering calculation method.