Abstract: Based on the axial compression load condition, the same weight of stiffened plates, the same distance between stringer and the same proportion of stringer section, the buckling characteristics and failure modes of “I” stiffened plates and “J” stiffened plates are studied by test and numerical calculation methods. The results show that the flexural capacity of “I” stiffened plate is the same as that of “J” stiffened plate, and the post-buckling capacity of the former is about 19.8% higher than that of the latter, and the error of eigenvalue buckling method from the test is about 11%. The main reason is that the eigenvalue theory does not consider the influence of stringer stiffness on the weakening of skin support during loading, so the calculated value is larger than the test value. Considering the influence of local effect and transverse stress component on matrix shear strength, a failure model of stiffened plate is developed. The error between the calculated value and the test value is about 8%, and the predicted failure mode is in good agreement with the test failure mode.