The invention discloses an electric swing mechanism, which comprises a motor (1), a reversing bevel gear (2), a worm (3), a moving part guide rail (4), a moving part (5), a pinion (6), an inner sector gear (7), a worm wheel (8), a worm wheel shaft (9), a gear case (10) and a gear case guide rail (11), wherein the motor (1), the reversing bevel gear (2), the worm (3), the worm wheel (8) and the worm wheel shaft (9) are located in the gear case (10); the moving part guide rail (4), the moving part (5), the pinion (6), the inner sector gear (7) and the gear case guide rail (11) are located outside the gear case (10); and the gear case (10) is of an upper opening structure. Compared with the prior art, the electric swing mechanism has the advantages that the size of the mechanism can be effectively reduced and the load bearing capacity is improved by adopting driving of the motor and transmission of the inner sector gear.