Due to the complicated structure and high precision requirement， the subordinate frame structure of aviation is still mostly made of aluminum alloy by CNC machines. In order to explore the feasibility of integrated forming solution for composite frame structure， this paper studies the resin transfer molding （RTM） method of a thin-wall composite frame with longitudinal and transverse stiffeners and partial flanging structure characteristics. Simulation results show that the full （0/90）₈ layer combination can reduce the warping deformation of the structure to the greatest extent， which was also verified by the actual manufacturing results. The flow simulation results show that surface-injection method can significantly reduce the filling time and pressure compared with point-injection and line-injection plans. By combining the optimized scheme with automatic laying-up blanking， pultruded filling material and other automatic processes， the integral insulation frame of composite material with qualified internal quality and similar sampling mechanical properties to the traditional autoclave forming process was successfully fabricated.