The invention provides a comprehensive monitoring and diagnosis system and method of state information of a mobile transformer. The comprehensive monitoring and diagnosis system of state information of a mobile transformer includes an intelligent wireless sensor which is used for collecting quantity of state of the transformer, an intelligent data exchange terminal which can obtain the data of theintelligent sensor in real time, a comprehensive monitoring system which selectively and deeply analyzes the reasons for equipment anomalies and searches equipment failure points and uploads the dataand the diagnostic result to a cloud platform expert diagnosis system, a cloud platform diagnosis service system which utilizes the intelligent data exchange terminal to movingly and comprehensivelymonitor the data uploaded by the equipment and comprehensively analyze operation state of the equipment, and evaluates the health of the transformer by combining failure case library so as to make anoverhauling strategy, and a background management system which logs in according to different user rights and can use different functions according to the rights, wherein the main function of the system is responsible for data management, data statistics, data analysis, and classified storage of monitoring data. The comprehensive monitoring and diagnosis system of state information of a mobile transformer can realize interaction between operation and maintenance staff and equipment management, and has practical significance for improving the monitoring efficiency of a substation and safe operation of the equipment.