Abstract: Introducing viscoelastic damping layer into composites is an effective method to improve the composite structural vibration characteristics. The vacuum assisted resin transfer molding (VARTM) process of sandwich composites with perforated silicone rubber was investigated by experiment and simulation. Firstly, the equivalent permeability of fiber reinforced materials and its combination with the flow medium were tested under constant pressure injection conditions. Then, the VARTM platform was set up to observe mold filling experiment in the laboratory. The resin filling model was established based on the RTM-Worx software. The validity of the simulation model was verified by comparing the experimental resin flow diagram and the filling area with simulated results at different time. Finally, the effects of the parameters such as the spacing between columns, the row spacing, the diameter of the holes in the damping layer and the "edge effect" on the resin filling time and the filling process were discussed. The results show that the simulation model can better predict the resin flow behavior, and unreasonable parameters of damping layer can affect the resin flow and even lead to defects.