The invention discloses a transformer substation relay protection device state monitoring system and method. The transformer substation relay protection device state monitoring system and method obtain transformer substation real-time picture by uninterrupted shooting of a translation zoom camera, include the steps: firstly, denoising processing is performed based on image smoothing, and then, image registration is performed, and then, a convolutional neural network technology is used for analyzing the image, so that whether the device is in a normal state or not can be accurately identified.And on the other hand, the camera can be installed and maintained without interrupting the power distribution service, and a plurality of devices can be monitored by a single camera, so that the costof the whole system can be greatly saved while the state monitoring accuracy is improved. Furthermore, aiming at the robustness problem of the model in a complex natural environment, the image registration scheme provided by the invention enables the model to maintain the performance under variable illumination conditions.