The integrated molding technology of T-shaped composite stiffened panel is an important means to realize light weight, high strength and low cost of composite product. The work based on the structural changes of the composite during the layering process, a skin-stiffener integrated T-shaped stiffened panel structure was designed. Through solid modeling, combined with the Young’s modulus, shear modulus, Poisson’s ratio and linear elastic constitutive model, the service behavior of the integrated T-shaped stiffened panel structure was simulated by finite element method. The results of finite element analysis show that the static mechanical properties of the integration composite T-shaped stiffened panel structure are better than those of the traditional structure. Meanwhile, the dynamic impact resistance of the integrated T-shaped stiffened panel can reach the similar level of the traditional T-shaped stiffened panel by adjusting the thickness of the skin. In addition, in order to verify the feasibility of the integrated molding technology of T-shaped stiffened panel, the integrated molding die with easy operation, low cost, uniform temperature distribution, and controllable thermal deformation was designed, and the integrated molding process of T-shaped stiffened panel was explored. The results have guiding significance for the quality control of the integrated molding of T-shaped stiffened panel.