Abstract： Objective To investigate the frequency of interleukin 1 receptor antagonist(IL Ra) gene polymorphism and its relationship to dibetic nephropathy. Methods The allele frequency and the genotype distribution of the polymorphism in second intron of IL Ra gene were studied in the groups of 148 non diabetic controls and 165 type 2 diabetes patients, with or without diabetic nephropathy. Results IL 1β and IL 1Rα frequencies were higher and IL 1Rα/IL 1β were lower in diabetes than those in control group.IL 1β was correlated with higher triglyceride, total cholesterol and fasting plasma glucose levels( P <0.05). The frequency of A 2 allele in control group was higher than those in all diabetic patients and patients with diabetic nephropathy group significantly ( P <0.05) but slightly higher than that in diabetic patients without diabetic nephropathy ( P >0.05). The frequency of A 2 allele in diabetic patients without diabetic nephropathy was higher than that in diabetic patients with diabetic nephropathy. Conclusion Diabetes patients with A 2 (240 bp allele) were less susceptible to diabetic nephropathy than those without A 2 allele.