The present invention relates to an electric power device identification model construction method and system, and an identification method of an electric power device. The electric power device identification model construction method comprises: marking electric power device targets in an infrared image respectively corresponding to each type of an electric power device, and obtaining a sample training set; inputting the sample training set into a RPN convolutional neural network to allow a loss function to have a minimum value, and outputting a target candidate frame; inputting the target candidate frame into a Fast-RCNN convolutional neural network, calculating the conversion weight value of the target candidate frame to a corresponding type according to a fully connected layer and a regression function, and employing the frame regression to obtain the Fast-RCNN parameters of the position of the target candidate frame being offset to a corresponding tag position; and setting a sharing convolutional layer learning rage as 0, and performing initialization of the RPN convolutional neural network and the Fast-RCNN convolutional neural network, performing training of an input infrared image in the RPN convolutional neural network according to the Fast-RCNN parameters, and obtaining a RPN convolutional neural network model; and inputting the target candidate frame into the RPN convolutional neural network model, updating the Fast-RCNN convolutional neural network to form a uniform Fast-RCNN network, and outputting an electric power identification model.