The utility model relates to a 24-volt power supply cabinet multi-state alarm color-change lamp identifying system. The system comprises a fixed support, a pick-up head, a shading tube, and a state alarm lamp which are arranged inside a power supply cabinet. The system further comprises an electronic circuit base plate already arranged inside the power supply cabinet. The pick-up head is arranged on the upper part of one side wall of the fixed support in the power supply cabinet. The front of the pick-up head enters the power supply cabinet. The rear part of the pick-up head is connected with a piece of given data acquiring processing equipment. The shading tube is arranged between the pick-up head front located inside the power supply cabinet and the state alarm lamp. The front of the pick-up head is located inside one end of the shading tube while the state alarm lamp is located inside the other end of the shading tube. The state alarm lamp is arranged on the electronic circuit base plate inside the power supply cabinet. The pick-up head acquires the fault color-change image information of the state alarm lamp on the electronic circuit base plate through the shading tube and further transmits the acquired fault color-change image information to the data acquiring processing equipment. The system with a simple structure achieves identification accuracy and facilitates timely fault detection. The system can be widely used in various power supply cabinet fault detection fields.