Abstract： Objective To investigate the relationship between apolipoprotein E(ApoE) gene polymorphism and type 2 diabetes mellitus,diabetic nephropathy in Chinese.Methods ApoE genotype was determined by PCR RFLP in 265 type 2 diabetes mellitus patients (106 without nephropathy,159 with nephropathy and the latter was divided into two subgroups:122 patients with proteinuria and 37 with renal insufficiency) and 110 non diabetic controls.Results ①Increased frequencies of allele ε2 and E2(E2/2+E2/3) genotype were found in the diabetic nephropathy group when compared with the non nephropathy group ( P =0.00894,0.00194 respectively).②No significant differences in ApoE genotype frequencies and allele frequencies were observed between type 2 diabetes mellitus and non diabetic control group (both P >0.05).Conclusion In Chinese,ApoE allele ε2 may be a risk factor for developing diabetic nephropathy complication.No correlation between ApoE gene polymorphism and type 2 diabetes mellitus was found in Chinese.