The invention relates to an accelerator of a circumferential-direction percussion bit. The accelerator comprises an outer cylinder, wherein one end of the outer cylinder can be connected with a drill collar in a sealed mode. A hollow lower connector is coaxially arranged at the other end of the outer cylinder in a penetrating mode, the other end of the lower connector is connected with the drill bit, and the lower connector is internally sleeved with a circumferential-direction percussion structure which can generate circumferential-direction percussion on the lower connector and is axially fixed; and a drilling fluid via hole penetrating in the axial direction is formed in the circumferential-direction percussion structure, and a throttling nozzle communicates with one end, away from the outer cylinder, of the circumferential-direction percussion structure. The accelerator of the circumferential-direction percussion bit overcomes the defects of the prior art, the stick-slip effect of the PDC drill bit existing in the actual using process can be effectively overcome, and the drilling speed is effectively improved.