The invention provides a battery monitoring system. The battery monitoring system comprises a plurality of battery packs, a plurality of battery management systems, a communication module and a monitoring platform, wherein each battery management system comprises a collection module and a master control module, and each collection module is used for collecting the battery information of the corresponding battery pack and transmitting the collected battery information to the master control module; each battery management system is provided with a unique serial number corresponding to the corresponding battery pack and the serial number is stored in the master control module; each master control module is used for transmitting the corresponding battery information and serial number to the communication module; the communication module comprises a plurality of receiving ends, a master control unit and a transmitting end; each receiving end is used for receiving the battery information andserial number transmitted by the corresponding master control module and storing the battery information and serial number in the master control unit, and the master control unit is used for integrating the battery information and serial number and classifying the integrated battery information; and the transmitting end is used for transmitting the battery information integrated and classified bythe master control unit to the monitoring platform.