A method and an apparatus for automatically computing work accuracy of a battery management system (BMS) includes the steps of controlling an automobile component simulation module to work, sending a work command to the BMS at the test moment t, and reading a prediction parameter, stopping working when the work command is completed, reading a work parameter and computing state of power (SOP) test accuracy of the BMS, determining whether a temperature of the battery pack exceeds a temperature threshold, if so, controlling a thermal management module to start working, and returning to the determination step, and otherwise, reading a stabilized parameter and performing computation to obtain state of charge (SOC) test accuracy of the BMS.