Objective: To compare the angiographic extent and severity of coronary artery disease in diabetic and non- ,rdiabetic patients. Methods: It was a hospital based, retrospective, descriptive study conducted in Cardiology Department,PGMI, Lady Reading Hospital, Peshawar from 2nd May, 2010 till 5th January, 2011.Computerized record of ~ jcoronary angiographies in the Catheterization laboratory was studied of all adult patients of age 38 years orabove. Coronary arteries were studied for severity of stenosis defined by using Quantitative CoronaryAngiography(QCA),for both groups. Using SPSS version 15, data was analyzed. A p value=0.05 wasconsidered significant. I Results: A total number of 200 patients were enrolled in the study with age ranged between 38-84 years. 152were males (76%) and 48 females (24%)so male : female ratio was 3:1.In this study there was difference between diabetic and non diabetic cases according to site and severity ofcoronary artery involvement, revealing significant statistical difference (p value <0.05) between diabeticand non diabetic among LAD, left circumflex (LCX) and RCAinvolvement. Conclusion: Diabetic patients have severe coronary artery disease as compared to non diabetics. Key Words: Diabetes, Non-diabetes, Coronary Angiography, Extent of Disease, Severity of stenosis.