Abstract: Objective To investigate the correlation between 25 hydroxy vitamin D3 （VitD3） and cholesterol（CHOL）triglycerides（TG） high-density lipoprotein（HDL） low density lipoprotein（LDL） 、 Urine albumin creatinine ratio（UACR） 、C peptide（C-P）、 glycosylated hemoglobin（HbA1c） in type 2 diabetes mellitus（T2DM）patients. Methods Serum vitamin D3（VitD3） 、CHOL、TG、 、HDL、LDL、,UACR、C-P and HbA1c detection index were determined in the 83 patients with established diabetes . And according to 25 hydroxy vitamin D3 level,the all of samples were divided into three groups,the VitD3 < 15 ng/ml for severe lack of group,15 ng/ml < VitD3 < 20 ng/ml for mild lack of group,VitD3 > 20 ng/ml for relative normal group . Results The serum VitD3 and CHOL、TG、HDL、LDL have no statistics significance among the three groups（P>0.05）. But,the level of VitD3 were negatively correlated with UACR and HbA1c; and positively correlated with C peptide; They have statistics significance among the three groups（P<0.05） . Conclusion Joint detection of VitD3、C-P and HbA1c can provide the basic information for prevention and control of diabetes,and has guiding significance in diabetes self-monitoring,and can be used as an index to assess the degree of diabetic nephropathy.

Key words: 25 hydroxy vitamin D3, C peptide, Glycosylated hemoglobin, Urine albumin, Creatinine ratio