Abstract: A developed computer code and a FEM/CV analysis software can combine to model any complex 3D composite parts and simulate the RTM mold-filling process. The simulation and experiments of I-shaped 2D plane with different processing parameters were investigated, and the results show that the mold-filling time is inverse proportion to pressure and penetrability, and direct proportion to resin viscosity. The experimental data are in good agreement with the numerical data, which validates that the simulation software is reliable to predict resin flow patterns and processing efficiency. The results can be further utilized to find the optimal processing conditions for RTM parts.