Abstract: Circular RNA (circRNA) is a novel type of non-coding RNA with covalently closed loops which plays an important role in the occurrence and development of type 2 diabetes. In this paper, the relationship between circRNA and type 2 diabetes in terms of the regulation of pancreatic β-cell function by circRNA and the metabolic activity of heart, kidney and other organs is reviewed, and the possibility of circRNA as a clinical diagnostic marker for type 2 diabetes and its complications is emphasized, hoping to provide reference and clues for the prevention, diagnosis and treatment of type 2 diabetes.