The method of the present invention is adapted to foam and crosslink a raw material including a rubber, a crosslinking agent and a foaming agent. The method includes the following steps: (1) a first crosslinking and foaming step, placing the raw material into a first mold, crosslinking and foaming the raw material to form a pre-molded body; (2) a second crosslinking and foaming step, withdrawing the pre-molded body from the first mold, placing the pre-molded body into a second mold after the pre-molded body being cooled down, crosslinking and foaming the pre-molded body to form a molded body; and (3) a third crosslinking and foaming step, withdrawing the molded body from the second mold, placing the molded body into a heating device after the molded body being cooled down, crosslinking and foaming the molded body to form a product.