The invention discloses a method for preparing a ping-pong bat through an HSM forming process. The method comprises the steps that thermally-self-expansion high-energy glue capable of being subjected to shaping pre-forming is placed in a product core material die and the die is tightly closed, the thermally-self-expansion high-energy glue capable of being subjected to shaping pre-forming is heated for 3-30 minutes at 80-100 DEG C, and micro-expansion is carried out, wherein a volume multiplying power before and after the micro-expansion is 1.01-1.5, a core material die cavity is fully filled with the thermally-self-expansion high-energy glue capable of being subjected to shaping pre-forming, cooling and die release are carried out, then the thermally-self-expansion high-energy glue capable of being subjected to shaping pre-forming is wrapped with a fiber prepreg and placed in a forming die, and the die is tightly closed, and the thermally-self-expansion high-energy glue capable of being subjected to shaping pre-forming is heated for 10-60 minutes at 120-180 DEG C, wherein the thermally-self-expansion high-energy glue capable of being subjected to shaping pre-forming continues to be heated to generate an expansion force from inside to outside, and the fiber prepreg is subjected to high-temperature curing forming; and cooling and die release are carried out, and a product is taken. The ping-pong bat prepared by the method disclosed by the invention is high in strength and low in reject ratio.