The invention discloses a transmission mechanism of a tail end manipulator of a robot, relating to a transmission mechanism. The invention aims at solving the problems of complicated structure, low reliability, poor self-locking property and the like in the traditional tail end manipulator of the robot. Worm wheel shafts penetrate through a front side wall, two rib plates and a rear side wall of a box body from front to back, staggered teeth worm wheels arranged between the two rib plates are arranged in the middles of the worm wheel shafts through keys; one ends of the worm wheel shafts are in transmission connection with the front side wall of a supporting housing through first bearings; the other ends of the worm wheel shafts are in rotary connection with the rear side wall of the supporting housing through second bearings; and the two staggered teeth worm wheels are symmetrically arranged at two sides of a worm, and each staggered teeth worm wheel is meshed with a helical surface at the upper end of the worm. The two symmetrically arranged worm wheels are driven by the worm, so that the worm wheels reversely rotate at equal speeds to ensure that the worm wheel shafts symmetrically rotate, a worm gear mechanism symmetrically moving can be obtained, i.e. the symmetrical motion of the two worm wheel shafts is realized, therefore, the application field of the robot is widened.