Finite element software MSC.PATRAN/NASTRAN is applied to analyze the buckling behavior of stiffened composite panel under compress load. In addition, experiment on this kind of structure is conducted in order to obtain the stability performance, failure process and carrying capacity of the structure. It is found that the emulation analysis results are accordant with the test results, which validates the correctness of the modeling and computation. The experiment results indicate that the structure studied has a biggish post-buckling carrying capacity and the finite element method is suitable and can be used for the analysis of the stability of the structure, which offers a reference measure for the optimization design and engineering application of the structure.