Dacryocystitis is a common ophthalmic disease, and the main treatment of it is to abandon the obstructed nasolacrimal duct and create a new lacrimal drainage pathway through implanting a tube.For now, its pathogenesis is understood very limitedly.It is widely accepted that many factors take part in its occurrence, among which obstruction and infection play important roles.Recent researches have shown that there is lacrimal drainage-associated lymphoid tissue (LDALT) which changes remarkably in dacryocystitis, and significant differences in cytokines expression levels in tears between dacryocystitis patients and normal control have been found.In addition, the lacrimal duct has reactions similar to immune rejection to the silicone tube.All of these indicate that immune factors participate in the pathogenesis of dacryocystitis.Changes of immune tissue and macromolecular substances including the LDALT, cytokines, local tissue and cytokines after tube implantation were reviewed to analyze the changes and possible roles of immune factors in the pathogenesis of dacryocystitis.