The invention provides a multi-focus image fusion method based on discrete Tchebichef polynomial transformation and focusing evaluation, and relates to the technical field of digital image processing and machine visual sense. The method specifically includes steps: 1) performing segmentation processing on multiple images in need of fusion to obtain r m*n image blocks; 2) performing normalization on each image block, and performing discrete Tchebichef polynomial transformation on the normalized blocks to obtain corresponding discrete Tchebichef polynomial transformation coefficients; 3) regarding a ratio of the energy of higher-order transformation coefficients to the energy of low-order transformation coefficients as a focusing evaluation function, and fusing the multiple input images according to a fusion rule that the focusing evaluation value is maximum; and 4) performing consistency verification on the fused images to obtain a finally fused image. According to the method, the connection between the image discrete Tchebichef polynomial transformation coefficient and the image focusing degree is established, the fusion time is saved, and the fusion effect of the images is effectively improved.