Tongue diagnosis is a non-invasive, efficient, and accurate method for determining a person's physical condi-tion, and plays an essential role in disease diagnosis and health management. However, tongue diagnosis is easily influenced by the subjective experience of the practitioner and the light environment. In addition, tongue di-agnosis lacks clear quantitative indicators and objective records. This all limits the transmission and develop-ment of tongue diagnosis. Therefore, the acquisition and analysis of tongue information using image equipment, image processing and computer vision have become a hot research topic for the objectification of tongue di-agnosis. This paper reviews the research progress of tongue diagnosis objectification in Traditional Chinese medicine. The tongue image acquisition, color correction, segmentation, feature extraction and analysis, and disease prediction included in the study of tongue diagnosis objectification are reviewed. The shortcomings of current automated tongue diagnosis systems and future research ideas are also summarized to provide a ref-erence for further development of tongue diagnosis objectification.