Abstract: An auto-lockup and anti-lock device for rotary mechanism applied to beach buggy, golf cart, electric cart and any other rotary devices includes a rotor, stator, stopper arranged to the stator for travelling between a lock and release position against the rotor, a clutch serving to control the stopper, and an anti-lock unit for disabling the stopper during an incident power off. The clutch is activated to drive the stopper away to disengage and release the rotor during power on. The clutch will release the stopper so that the stopper can engage and lock the rotor after power off. The anti-lock will move to block the stopper from engaging the rotor while the rotational speed of the rotor exceeding a predetermined value. The anti-lock will release the stopper automatically while the rotational speed of the rotor dropping below the predetermined value.