The theory of "liver opens at the eyes" was first seen in Yellow Emperor's Internal Canon of Medicine， which is the ancient people's summary of the connection between the liver and the eyes. The theory of "liver opens at the eyes" suggests the characteristic of "co-damage and co-recover of liver and eyes". It has been found in clinical practice that liver diseases and eye diseases often occur together， and "liver and eyes co-recover" is an ideal choice. The key to achieving "liver and eyes co-recover" is to analyze its pharmacological material basis and mechanism. With the development of modern medicine， more and more evidence indicates that the liver and eyes have complex and close relationships in physiological and pathological aspects. In a pathological state， there is a phenomenon of "liver and eyes co-damage"， and after the intervention of traditional Chinese medicine， "liver and eyes co-recover" occurs. "Liver and eyes co-damage and co-recover" can be explained through the "co-material basis and co-action mechanism". On this basis， the research group tentatively proposed that the liver and eyes had "four common characteristics" （4CCs）， namely "co-damage， co-recover， co-material basis， and co-action mechanism" from the theoretical connotation of traditional Chinese medicine， clinical practice， and molecular biology. Additionally， the group also took the intervention of Prunella vulgaris， traditional Chinese medicine， for removing liver fire and improving eyesight on immune liver injury （ILI） and allergic conjunctivitis （AC） as examples to analyze 4CCs. This project aims to deeply analyze the scientific connotation of the theory of "liver opens at the eyes"， reveal the common characteristics and biological essence of liver and eyes， explore a new research paradigm of "liver and eyes co-recover"， and provide a reference for the study of common problems of multi-organ associated diseases.