Abstract: This paper introduces the oil production mechanism of the new-type hydraulic drive double-screw pumps,and the optimum design method for the double-screw pump lift system with hydraulic drive.The optimization design principle is established.According to the principle,the node analysis method and optimization technique are employed to study the oil-well production system based on the oil well production,inherent properties of pump systems,and the coordination of the whole assembly.When pumps operate with the highest efficiency,the energy lost of the whole assembly gets the lowest,that is,the pressure value of wellhead power fluid under prescribed output of a well taken as the design target is the minimum.In accordance with the basic theory and working characteristics of single-screw hydraulic machinery,a calculation formula is figured out by taking the specific conditions of oil wells of Liaohe offshore oilfield into account.It is of universal significance for the design of such single-screw pumps,providing technical support for the systematic design of such hydraulic drive double-screw pumps.What’s more,it discusses the key techniques and solutions to the development of model pumps.