The invention discloses a production process of a foamed TPU (Thermoplastic polyurethane) sole. The production process comprises the following steps: mixing TPU particles and a foaming agent, forming a melt by an extruding machine and injecting into a first sole mold, keeping the temperature of the first sole mold for 3-5min after the melt is injected, cooling to the room temperature and demolding the first sole mold to obtain the foamed TPU sole, wherein the weight percentage ratio of the TPU particles to the foaming agent is 100:(1-10), the injection speed of the melt is 50-60mm/s, and the injection pressure is 10-15Mpa, and the temperature of the first sole mold is kept to be at 120-130 DEG C in a melt injection process; according to the production process, the mixture of the TPU particles and the foaming agent is injected into the first sole mold by the extruding machine at certain injection speed under specific injection pressure, the mixture is foamed in the first sole mold to obtain the foamed TPU sole, thus, the foamed TPU sole has the advantage of high rigidity of the TPU material, and as TPU has micro pores, the foamed TPU sole has light weight and good damping performance.