Abstract: A kind of image fusion algorithm based on wavelet transform was proposed and it is appropriate for fusion of multi-focus images. First, multi-scale decomposition of each source image was gotten through wavelet transform, the selection scheme of high-frequency and low-frequency coefficients was discussed. While choosing high-frequency coefficients, the SSIM matrix and the edge energy matrix were calculated by using slip gauss window, finally, fusion images were achieved according to a fusion operator which combines structural similarity (SSIM) with edge operator. The results show that the improving algorithm greatly inhibits the ringing effect, effectively avoids the information loss in the fusion process and the effect of fused image is better.