A system for testing a DC power supply performance includes a load module electrically coupled to the DC power supply, a switch module electrically coupled to the DC power supply, a control module electrically coupled to the load module and the switch module respectively, and an indication module electrically coupled to the control module. The control module includes a judge module and a comparison module. The judge module is configured for receiving DC voltage signals from the DC power supply; wherein the judge module is capable of turning on when the DC power supply is normal. The comparison module is configured for comparing the DC voltage signals with a reference voltage; wherein the comparison module is capable of outputting a control signal when the DC voltage signals are greater than the reference voltage. The indication module is configured for receiving the control signal and indicating status of the DC power supply.