The utility model relates to a management system for monitoring the state of a transformer station DC system device. The management system is characterized by comprising a transformer station intelligent equipment operating state information acquisition platform, a transformer station equipment data information acquisition device, and a monitoring center data concentration management platform, wherein the monitoring center data concentration management platform is respectively connected with the transformer station intelligent equipment operating state information acquisition platform and the transformer station equipment data information acquisition device. While achieving the real-time acquisition and management of the information of all the DC system devices, the management system is also capable of monitoring mono-battery voltage, heavy current DC internal resistance test, and checking capacity test in an on-line manner. Moreover, the management system allows online monitoring of direct current cabinet voltage stabilization, current stabilization, and ripple coefficient in a real-time manner. The system software adopts advanced storage battery failure determining model to comprehensively measure and determine the battery performance and provides display and early warning about failure cell under float charging operation state, and can also carry out efficient activated maintenance for the battery.