The invention discloses a battery managing system (BMS) testing platform comprising a testing platform main control computer, a high-precision cell voltage simulator, a high-precision large-current constant-current source, a high-precision thermotank, a battery managing system to be tested, a whole vehicle controller simulator and the like which are connected by CAN buses. The battery managing system is connected with a cell box air cooling device, a vehicle relay assembly and the like. The battery managing system testing platform can truly simulate the output state of a battery, comprising single cell voltage, total voltage, charging and discharging current, temperature and the like of the battery, can complete various communication and command functions, protection functions, battery heavy current applying process between the battery managing system and the whole vehicle, and the test and the verification on the functions of overhead protection and the like of the battery. The invention can carry out testing evaluation on the data collection precision of the battery managing system, the evaluation precision of the charge state of the battery and the like.