Type 2 diabetes (T2D) has become a common chronic disease worldwide. Pancreatic β cell dysfunction, together with insulin resistance, is among the main causes for the pathogenesis of T2D. However, the dynamic changes in the number and function of β cells and the molecular mechanism of irreversible damage in the pathogenesis of T2D are still unclear. A thorough analysis of the mechanism underlying β cell dysfunction will provide a theoretical basis and molecular targets for the development of new and more effective individualized therapies for diabetes.