Aiming at a typical multi-walled box-segment composite component in the aviation field, the PAM-RTM software is used to assist in the design and optimization of resin flow channels for the RTM process. Through comparative analysis, the influence pattern of different resin flow channels on the resin filling times in the RTM process is obtained, and the injection scheme is optimized. Additionally, the relationship between different injection pressures and the resin filling times is analyzed, indicating a negative correlation between injection pressure and filling time. Under the premise of ensuring forming quality, the resin injection pressure is optimized. Finally, the process validation is conducted for this typical structure, and the forming quality of the test piece is tested. The results indicate that the test piece exhibited good forming quality, with no defects exceeding the specified standards. The research results provide support for the application of RTM process in complex aviation composite structures.