The depth of field for imaging equipment is limited, the problem of out-of-focus of part of the acquisition image.An effective multi-focus image fusion algorithm is proposed, to further improve the contrast and sharpness of fused image. Firstly,the source image is decomposed into approximate subbands and detailed subbands by NSCT; Secondly,the FMO and ISML were used to combine the approximate subband coefficients and the detailed subband coefficients respectively;finally, the fused image is obtained by inverse NSCT. Experiments were conducted using a gray scale multi-focus image dataset, and comparative analysis with commonly used multi-focus image fusion algorithm shows that, the proposed fusion algorithmhas superior performance in terms of visual inspection and 7 commonly used objective evaluation indicators.