To address the problems of color distortion, low contrast, and blurred vision in degraded underwater images, an underwater image enhancement algorithm based on high and low frequency component fusion is proposed. First, multi-scale retinex algorithm is used to estimate high frequency components. Then, contrast-constrained adaptive histogram stretching is performed to enhance the global contrast while highlighting details. To prevent noise generated during image stretching from affecting the image quality, guided high frequency components are denoised via guided filtering. Then, the original image and high frequency components are divided to obtain low frequency components, and the multi-scale detail extraction method is used to obtain detailed information. Finally, the noise-removed contrast-enhanced image and the high and low frequency detail image are linearly weighted and color corrected to obtain the final underwater clear image. Experimental results show that the proposed algorithm can effectively enhance the image contrast and details and significantly improve the visual effect of the image.