The utility model discloses a mechanical gravity vibration device of a reduction kiln. The mechanical gravity vibration device can work normally under the environment of high temperature (200 DEG C-500 DEG C) of thermal radiation. The mechanical gravity vibration device comprises a rack, a lifting support, an impact head, a spring, a counter weight, a pulling rope and a driving device, the rack comprises a crossbeam and supports arranged at two ends of the crossbeam, and the lifting support is vertically arranged in the middle of the crossbeam. The impact head is located at the lower end of the lifting support, and the head of the impact head vertically penetrates the crossbeam. The spring is arranged on the impact head and located between the tail of the impact head and the crossbeam. One end of the pulling rope is connected with the driving device while the other end penetrates the upper end of the lifting support to be connected with the counter weight. The mechanical gravity vibration device is mainly composed of mechanical parts and the high-temperature-resistance pulling rope, so that the device can complete the vibration process smoothly under the environment of thermal radiation outside a barrel of the reduction kiln, frequency and time of shutdown are reduced, working efficiency is improved, vibrating effect is improved obviously, production of the reduction kiln is increased, and quality of produced products is improved.