Abstract: Deafness is one of the common causes of disability. Its occurrence and development are affected by many factors. A large number of basic clinical studies have shown that cadherin 23 is a cellular structural protein closely related to the function of the inner ear. In this study, the molecular structure and biological function of cadherin 23 were reviewed, the role of cadherin 23 in hair cell development and its correlation with clinical symptoms were described, and the important role of cadherin 23 in maintaining the morphological and functional integrity of hair cell bundles in the inner ear was revealed. At the same time, the application of different mutation forms of cadherin 23 gene(Cdh23)encoding cadherin 23 in clinical detection was explored, aiming to provide a new direction for early clinical gene diagnosis research of deafness.