The invention relates to a discharge assisting and liquid increasing device of an oil pumping machine, which is characterized by mainly comprising an upper joint, a core pipe, a spring, a sealing bowl assembly, a sealing ring, a steel ball, a ball seat and a lower joint, wherein the core pipe is formed into a core pipe whole by inserting, fixing and connecting a core pipe body A and a core pipe body B, the upper end of the core pipe body A is in threaded connection with the upper joint, a sealing frame in sliding fit with the core pipe body A is arranged on the core pipe body A, a bowl-shaped sealing expansion ring is sleeved on the sealing frame, the sealing ring is arranged at the lower part of the sealing expansion ring, four axial semicircular long slots which are uniformly distributed in the inner hole of the core pipe body B are coincided and connected with the inner holes, a ball blocking rod is arranged at the upper part of the inner hole of the core pipe body B, the ball seat is arranged at the lower part of the inner hole of the core pipe body B, the steel ball is arranged on the ball seat, and the lower end of the core pipe body B is in threaded connection with the lower joint. The invention has the advantages that the discharge assisting and liquid increasing device is connected with an oil pumping rod string in segments and is used for lifting the crude oil in an oil pipe in segments, and the ascending resistance of a plunger piston is lightened, thereby reducing the internal leakage of a pump barrel and increasing the fluid production rate of an oil well.