The invention discloses a hydraulic compressing device based on end-face friction. The compressing device comprises an adjusting cushion (7), wherein an upper cylinder body (1) and a lower baseplate (8) are arranged at the upper part and the lower part of the adjusting cushion (7) respectively; a compressing sheet (2) with the thickness thereof being smaller than that of the adjusting cushion (7) and the longitudinal position thereof being limited between the cylinder body (1) and the baseplate (8) is sleeved on the outer ring of the adjusting cushion (7); the outer ring of the compressing sheet (2) is fixedly connected to the end face of a rotator (22) to be braked; a hydraulic cavity and a plunger (3) in the hydraulic cavity are arranged on the lower end face of the cylinder body (1); the bottom part of the plunger (3) is propped against the upper end face of the compressing sheet (2); the cavity above the plunger (3) is connected with an oil feeding system via an oil hole (21); the upper part of the plunger (3) is connected with a return spring (13); and the upper end of the return spring (13) is fixed on the upper cover of the hydraulic cavity. The compressing device of the invention has the characteristics of ingenious structure, simple compressing method, higher braking torque, simple assembly and low cost.