In order to solve the problems of color distortion,low contrast and fuzzy details of underwater images caused by medium scattering and absorption,an improved algorithm of dark channel prior for underwater image enhancement is proposed.White balance processing is adopted to correct the blue (green) color deviation of the underwater image,and homomorphic filtering is conducted on the L component of the image in LAB space,so as to obtain a dark detail highlighted image.In RGB space,CLAHE processing is conducted to enhance the image contrast and solve the image atomization problem,and MSRCR processing is conducted to improve image color saturation and equalize image brightness.The fusion weight coefficient is calculated based on the dark channel prior image,and weighted fusion of the three images and detail enhancement are conducted to obtain the final enhanced image.The experimental results show that the proposed algorithm can effectively remove color distortion,and the enhanced image presents high contrast and clearer details.