Abstract: In order to improve the safety of electric vehicle operation, a remote monitoring and service system of electric vehicle based on 4G network is designed and implemented, the system integrated the data of battery and motor obtained by CAN bus, send to monitoring server center through 4G network, server stores, analyzed and received the information, the system provided users with the functions of user info query, vehicle state information query, vehicle track query, battery fault information alarm and car fault alarm, to achieve the monitoring function of electric vehicles. The system was tested, and the designed system can realize real-time monitoring and fault diagnosis of electric vehicle.