The work aims to determine the RTM parameters of the launcher container cover through the finite element analysis technology, so as to reduce the waste of man power & material resources and product costs. The numerical simulation of resin flow process of cover RTM was carried out. The resin flow forward position and pressure distribution results of online injection - point outgoing and point injection - point outgoing were compared accordingly when the injection molding pressure was 0.2 MPa or 0.4 MPa . In order to balance the cost and efficiency, 0.4 MPa was selected as the RTM injection molding pressure. Online injection - point outgoing process was used to get stable resin flow forward shape, which could effectively prevent the generation of dry patches. As analysis results are well anastomotic with the experiments, they can effectively guide the mold design in the RTM process, reduce the high cost and low efficiency of "trial and error method", and play an obviously positive role in improving the manufacturing level of composite components.