The invention relates to a viscous damper with an axial spacing device, which comprises a left spherical hinge seat, a piston rod, a piston, a damping cylinder body, a balancing bar, a right spherical hinge seat, damping medium, a combined disk spring, a spacing cylinder body, a pressure ring A, and a pressure ring B. The spacing cylinder body is arranged between the damping cylinder body and the right spherical hinge seat, internal threads are arranged at two ends of the spacing cylinder body, the left end of the spacing cylinder body is connected with the damping cylinder body via the pressure ring A, the right end of the spacing cylinder body is connected with the right spherical hinge seat via the pressure ring B, the length of the balancing bar is extended into the spacing cylinder body, a threaded small circular cylinder is arranged at the right end of the balancing bar, and the combined disk spring is installed on the small circular cylinder. Compared with the prior art, the inventive viscous damper can meet the technical requirements on dynamic energy dissipation for shock resistance, and meet the technical requirements on static load and excessive displacement limit.