Due to the scattering and absorption of water medium and underwater particles, there are some problems in underwater image, such as low resolution and contrast, fuzzy details, color distortion and so on. Aiming at these problems, this paper proposes an underwater image sharpness enhancement algorithm based on light field imaging. According to the dark priori theory and the single-scale Retinex theory, the underwater scattering imaging model is established to enhance the sharpness of the image, and the image enhancement effect of the scattering imaging model is optimized by using the multi angle characteristics of light field imaging, so as to further improve the quality of underwater imaging image. The experimental results show that the underwater scattering model and multi view optimization algorithm can effectively improve the quality of underwater image.