The high-efficiency oil-water separation device designed in this paper is mainly composed of water storage tank,separation box,buffer mechanism and other structures.Through the narrow through hole in the buffer mechanism,the speed of water flow into the first feed pipe is slowed down,and the stop valve is set on the first feed pipe,so as to accurately control the speed of the oil and water mixture into the separation device,reduce the kinetic energy of the oil and water mixture,so that the settlement difficulty is reduced,and the oil and water mixture can be better separated.At the same time,the oil-absorbing cotton is arranged in the separation tank to further improve the oil-water mixture.