Type 2 diabetes is one of the fastest growing metabolic diseases in the world. It is predicted that the number of diabetes patients will increase to 642 million by 2040, of which 30%～40% will develop into diabetes nephropathy. Insulin-like growth factor-1(IGF-1) is a peptide composed of 70 amino acids, which is homologous to insulin and has insulin-like effects. It also plays an important role in cell proliferation, differentiation, apoptosis, metabolism, embryonic development, tumor occurrence, and development. In recent years, many studies have found that IGF-1 directly or indirectly participates in the pathophysiological process of diabetes, and is closely related to the occurrence and development of diabetes nephropathy through insulin related signaling pathways. Cyclic glycine proline(cGP) is a metabolite of IGF-1 and participates in the regulation of IGF-1. cGP/IGF-1 represents the biologically active IGF-1. This article reviews the possible role of IGF-1 in type 2 diabetes and type 2 diabetes nephropathy, and provides new ideas for its treatment and prevention.