Jack

The utility model provides a jack, which belongs to the field of mechanical technology, and solves the problems that an existing hydraulic jack uses an external oil pipeline to easily generate leakage of hydraulic oil, simultaneously exposed pipelines are easily corroded and the like. The jack comprises a base, a motor, an oil pump, an oil box and a jacking device which are arranged on the base, wherein a fixing structure which can lead a side wall of an oil tank, which is provided with an oil supply port to fixedly connect with the base is arranged between the oil tank and the base, and the base is further provided with an oil inlet channel and an oil outlet channel which are communicated with an oil tank inner cavity. The jack effectively prevents the oil tank from leaking, thereby guaranteeing the stability of jacking action, and prolonging the life. Simultaneously, the jack has simple and compact structure, and strong practicality.