The invention relates to an insulator external discharge mode identification method based on an ultraviolet map. The method is characterized in that the method comprises the following steps: a) to begin with, carrying out non-contact detection on insulator external discharge by utilizing an ultraviolet imager and forming an ultraviolet discharge image; b) carrying out gray scale processing on the obtained ultraviolet discharge image and converting a color picture into a binary gray image; c) then, carrying out mathematical morphology filtering on the binary gray image to obtain a clear ultraviolet light spot binary gray map; d) carrying out constant-torch characteristic parameter extraction on the ultraviolet light spot binary gray map obtained after filtering, and seven constant-torch characteristic parameters are extracted; and e) inputting the seven constant-torch characteristic parameters into a neural network to carry out discharge type mode identification, and outputting the identification results. Experiment shows that the ultraviolet detection map is utilized to carry out mode recognition of insulator external discharge, and the method has the advantages of high identification degree and simple method.