Abstract: Liquid infiltration processing is advanced technique for the preparation of fiber reinforced metal matrix composites (FRM).The morphology and properties of FRM are influenced greatly by the infiltration and filling process. In this paper the resistance to the process and the filling form of FRM are studied. It is found that the filling form is determined by the distribution of fibers and the wettability between fibers and matrix. The way of controlling the infiltration and filling process to get perfect FRM was discussed by controlling the distribution of fibers,improving the wettability between fibers and matrix, and optimizing the parameters of the processing.