Abstract: Type Ⅰ autoimmune pancreatitis (AIP) is a type of pancreatitis with a predominantly inflammatory and fibrotic nature and is an IgG4-related disease. The pathogenesis of type Ⅰ AIP is still poorly understood, but it is generally believed that it is the result of a combination of genetic, environmental, and immune factors. In recent years, many advances have been made in the cellular and molecular mechanisms of the pathogenesis of type Ⅰ AIP. Therefore, this article aims to review the research progress of the pathogenesis of this disease from the immunological perspective.