The skirt bonding properties of the composite case was analyzed by using the numerical method. The finite element model of the filament wound case was established. The contact of the skirt bonding interface was defined with the cohesive zone model. The damage failure criterion was employed and the debonding of the interface was simulated to predict the ultimate load of the skirt structure. Moreover, the distributions of the axial strain and the hoop strain on the case and the shear stress in the interface were investigated. The effects of the elastic modulus and the bonding length on the ultimate tensile load were studied. Numerical example shows that the results have a good agreement with the experimental data, which can provide validity for the present method. The proposed method can be applied to the optimal design of the skirt structure.