The invention provides a large hydraulic damper. The large hydraulic damper comprises a right pin head, a right end cap, a cylinder body, a piston assembly, a piston rod, a left end cover, a left pinhead, a plug, an oil filling hole, an auxiliary piston rod and a temperature compensation device. The large hydraulic damper adopts the method of combination of a damping flow passage and a first flowpassage to realize low-speed friction resistance and fast locking performance of a damper, the outer diameter of the auxiliary piston rod is the same with the outer diameter of the piston rod, so that the volume of oil change on the left and right sides of the damper is the same; the arrangement of an auxiliary oil tank of the damper is reduced, and the boundary dimension of the damper is reduced; a temperature compensating device is used for forming a temperature compensating cavity for accommodating and supplementing the change of the oil volume when the temperature changes, and the temperature variation is prevented from affecting the working performance of the damper; the temperature compensation device is located inside an inner hole of the auxiliary piston rod, and the boundary dimension of the damper is reduced; the structure is simple, processing technology performance is good, the product quality is ensured, and the product reliability is improved.