Chronic dacryocystitis(CD)is a disease caused by microorganism infection secondary to nasolacrimal duct stenosis or obstruction. Its pathological changes are of great significance to the diagnosis, treatment and prognosis of patients. This paper summarizes the characteristics of the pathological changes of the lacrimal drainage system and surrounding tissues by reading a large number of domestic and foreign literatures on chronic dacryocystitis in recent years, aiming at improving clinicians' understanding, doing better diagnosis, treatment and prognosis judgment, and providing ideas for further research.