The light propagation under water is influenced by the absorption of water and particles, which may result in low contrast, noise, and color deviation of underwater images.Aiming at the problem that the enhanced image of the traditional homomorphic filtering algorithm still has foggy blur and dark color, an improved underwater image enhancement algorithm is proposed, which fuses the improved homomorphic filtering with multi-scale Retinex.Firstly, the single-scale Retinex algorithm based on bilateral filtering is used to correct the color of the original image.Then, the modified image is filtered by constructing a corresponding Butterworth notch filter.Finally, the image enhanced by homomorphic filtering and the image after color modification are fused at multiple scales.Experimental results show that this method can effectively suppress color offset and improve image resolution.