Wrist of industrial robot

The invention discloses a wrist of an industrial robot. The wrist comprises a forearm and a wrist shell which is rotatably connected to one end of the forearm. The other end of the forearm is provided with a vertical motor and a vertical reducer. An output shaft of the vertical reducer is connected with a left belt pulley. The wrist shell is internally provided with a horizontal motor and a horizontal reducer and connected with a right belt pulley through a fixing shaft. Transmission between the left belt pulley and the right belt pulley is facilitated through a transmission mechanism. According to the arrangement, bevel transmission is omitted, noise is reduced, and mechanical transmission is avoided, thus the wrist moves independently in the horizontal direction and vertical direction without coupling relationship, and machine precision is ensured. Besides, the vertical motor and the vertical reducer are arranged at the front, leading to small size of the wrist shell, and a synchronous belt is arranged at the low-speed end to prolong the service life thereof.