The invention discloses an on-off control method for a plug connector of a power battery. The on-off control method comprises following steps: 1) system initialization; 2) detection of vehicle speed; 3) detection of a request signal for closing a cabin door; 4) detection of the request signal for opening the cabin door and an impact signal and the like. The on-off control method for the plug connector of the power battery has following beneficial effects: a controller is used for collection and logical judgments of complete vehicle signals and executing opening and closing action to a motor by replacing a conventional method of manual pull and plug; synchronous operation of multiple battery packs can be greatly improved; security threats to operators are reduced; and double benefits are obtained.