The fluid dynamics law of differential pressure vacuum injection process was studied, and the corresponding reaction kinetic model, reaction molding viscosity model and chemical rheological model were established to analyze the forming mechanism. Secondly, combined with orthogonal experimental design theory and CAE technology to design and simulate orthogonal experiments, and use MPI software to simulate the injection molding process and computer-aided analysis of the quality of the cast parts, explore the influence of the main process parameters on the quality of the cast parts, determine the key process parameters affecting the quality, summarize the adjustment law of key process parameters, determine the optimized process parameter combination, and provide theoretical support for the actual injection process parameters.