Abstract:In recent years, a large number of studies have found that vitamin D levels in type 2 diabetes mellius(T2DM) patients are generally lower than those in normal people. Whether there is some causal association of vitamin D deficiency and T2DM is unclear. Some studies have proposed that vitamin D deficiency may be involved in the occurrence and development of T2DM, and vitamin D supplementation has the potential to be a complementary treatment for T2DM. As the incidence of T2DM increases year by year, all of the above problems will become the focus of our attention, so this paper makes a preliminary exploration and summary of the above problems through the form of summary.