Abstract: A novel fusion algorithm for multi-focus images was proposed using Uniform Discrete Curvelet Transform(UDCT) for its characteristics of multi-scale; multi-direction and low redundancy. First, the source images were decomposed into several subbands using UDCT. Then, according to the characteristics of multi-focus images, the coefficients of low-frequency subband were fused with a scheme based on the sum-modified-laplacian; the coefficients of high-frequency subbands were fused with the fusion rule based on local energy; and the consistency of the fused coefficients was verified. Finally, the subband coefficients were reconstructed, and the fused image was obtained. The experiment results indicate that the proposed method can effectively fuse the directional information and detailed features of source images, and suppress pseudo-Gibbs phenomena of fused image; compared with other fusion methods, such as those based on Laplacian pyramid transform, discrete wavelet transform and contourlet transform, this method obtains better fusion quality in terms of both visual and quantified measure.