The invention relates to a mobile charging pile and its usage method. The mobile charging pile includes: a management system, a charging system, an energy system, a driving system, a communication system and an auxiliary system. Among them, the management system includes the battery management system and the energy management system, which is responsible for integrating and controlling other systems; the energy system includes batteries and chargers, which are used to store and provide electric energy for other systems; the charging system includes DC charging piles, inverters, AC Charging piles and 220V emergency sockets are responsible for converting electric energy and charging electric vehicles; the drive system includes drive circuit boards, motors, steering rods, and wheels to control the movement of charging piles; the communication system includes mobile phone clients and backgrounds, responsible for contacting car owners , mobile charging pile and its person in charge; auxiliary systems include DC converters, switches, shutters, warning lights, shelves and housings, which are used to assist the operation of other systems. The invention has the advantages of convenient reservation, flexible maneuvering and unlimited charging positions.