As a transit station for power transportation, substation is an important infrastructure for city operation and people''s life. During the operation of the substation, the problem of untimely detection of the temperature of equipment operation due to the remote location, which does not support the direct detection by robots and drones, often occurs. The traditional substation equipment defect recognition algorithm is based on machine learning algorithms, which has low accuracy, is only suitable for the defect detection of a single equipment category, and is susceptible to environmental influences. Based on this, the article comes out with an improved method for recognizing infrared defects of substation equipment. First, target equipment detection based on Faster R-CNN is performed for six types of substation equipment including bushings, insulators, wires, voltage transformers, lightning rods, and circuit breakers in order to realize the precise location of the equipment; then, different classes are identified based on Sparse Representation Classification (SRC), so that the actual labels of the input samples can be obtained; and finally, based on the Temperature Threshold Discriminant algorithm, temperature anomaly defects are recognized in the device region. The article algorithm realizes the recognition and detection of devices under infrared images, using the article algorithm to detect the infrared images of six classes of devices, the accuracy rate reaches 91.58%, the defect recognition rate of different types of devices is 97.63%, and the defect recognition accuracy rate reaches 87.62%. The experimental results show the effectiveness and accuracy of the method.