In order to achieve discharge point location and electrical equipment fault diagnosis, UV imagers need to register UV and visible light images from different sensors. Due to the large difference between the imaging principles of ultraviolet and visible light images and the difficulty in feature extraction and matching, a mutual imagebased UV and visible image registration algorithm is proposed and applied to the UV imager for realtime registration. Firstly, the mutual information in the ultraviolet and visible light images is calculated. The mutual information is used as the similarity measure. The image is transformed by the rigid body transformation model. The image transformation parameters are obtained by the 1+1 evolutionary algorithm to obtain the spatial transformation parameters of the optimal similarity measure, and the effectiveness of the proposed algorithm is verified by simulation and UV imager.