Purpose To investigate the effect of COS-Se on plasma glucose, lipid levels and insulin levels in rats with type 2 diabetes. Methods After the rat model of type 2 diabetes was established by a single injection of low dose streptozotocin after high fatty diet, the animals were divided into control group, COS-Se group, Se group and COS group. Other 10 rats were employed as normal control group. The levels of blood glucose, total cholesterol and insulin in the serum were determined. Results COS-Se group was compared with the Se group and COS group...