1.5 million people died due to diabetes and more than half millions of them died because of diabetic kidney diseases in 2015. In Ethiopia, the frequency of chronic complications of diabetes is high and an increased occurrence of nephropathy, peripheral neuropathy, hypertension, and retinopathy was observed with longer duration of diabetes. However, there is limited data on the assessment of renal function among Diabetic patients at country level in general as well as specifically in Asella Referral & Teaching Hospital. Retrospective study method was used and Cockroft-Gault formula was used to calculate the estimated Glomerular Filtration Rate. The data were analyzed using SPSS version-20 software and the Pvalue was calculated to see the statistically significant association (p-value < 0.05) among different parameters. Among the total of 189 study subjects, 123 (65.1%) was found to have evidence of renal damage. Of all 123 patients having renal damage, 76 (40.2%) was stage 2, 4 (2.1%) was stage 4. Diabetic patients whose age is >50 were 0.276 times at risk of developing diabetic renal damage than those aged ≤50 (AOR=0.276, 95% CI (0.133-0.574) p=0.001)