The utility model discloses a hydraulic self-balance transmission sealing device and pertains to the technology field of the switching device of a piston-pushing material centrifuge hydraulic oil, containing an oil outlet dynamic plate and an oil storage dynamic plate that are telescoped in a hollow shaft side by side. The oil storage dynamic plate is embedded with a switching static plate; outside the oil storage dynamic plate is connected with an outer retaining ring; outside the oil outlet dynamic plate is telescoped with an oil inlet static plate; besides, the switching static plate and the oil inlet static plate are connected fixedly and the oil outlet dynamic plate and the oil storage dynamic plate are connected fixedly; the outer circumference of the oil inlet static plate is provided with a radial oil inlet hole and an axial oil inlet hole; the switching static plate is provided with a V-shaped vittae; the oil outlet dynamic plate is provided with a direct oil through with a slope; the radial oil inlet hole, the axial oil inlet hole, the V-shaped vittae and the direct oil through form a pressure oil passage. The utility model realizes the transformation of radial oil inlet into synchronously rotary axial oil outlet and dynamic self-balance, besides, the utility model can self adjust the oil mass to realize stepless oil supply; the utility model is mainly applied to the switching device of a piston-pushing material centrifuge hydraulic oil.