The work aims to introduce the realization method and principle of typical image colorization, summarize and analyze the characteristics and application scenarios of image colorization method, and put forward the research direction and development trend of image colorization technology in the future based on the latest research progress. According to the classification of image colorization technology, the relevant methods in the research field of image colorization technology at home and abroad were systematically introduced, and the image colorization method and its characteristics based on partial differential equation, image fusion and image segmentation were compared and analyzed. In future research work, combining the image colorization technology with other disciplines, using computer rapid processing capability, hardware advantages and rich software resources, and selecting the appropriate image colorization method according to the application scene and algorithm characteristics, can better improve the image processing efficiency and visual effects, and achieve precise application of image colorization.