Abstract: The vacuum infusion molding process is becoming popular as a new type of Liquid Composites Molding Processes. In the paper, the vacuum infusion molding process based on grooves was investigated by experiments, and the parameters of width, depth and spacing for flow grooves and spacing for supply grooves were optimized according on the molding experiments and various factors that had influence on the mold filling process were discussed. Furthermore, the whole vacuum infusion procedure is introduced in detail, taking the manufacture of a sandwich panel in one infusion for a case.