Objective: The diameter of coronary arteries varies greatly among general population. The knowledge of variations in coronary arteries helps the clinicians to define abnormalities and plan the treatment. Hence, the present study was aimed to study common primary variations of coronary arteries by angiography in Indian population. Methods: The data for this unicenter, retrospective, observational study was collected from general hospital, Maharashtra, as patient data sheets and coronary angiograms (CAG) reports for a period of 1 year and 8 months. The CAG were studied for variations in main trunk diameter of coronary arteries and range of diameters of coronary arteries. Results: A total of 400 conventional CAGs were observed, of which 17 angiograms showed anatomical variations. The diameter of left coronary artery was more than right coronary artery (RCA) in 90.5% and less in 9.5% of CAGs. Statistically significant difference was observed on comparing the mean diameter of RCA (3.40(0.81 mm) and left coronary artery (4.52(0.95 mm; p<0.001). The range of diameter of RCA (1.8 to 6.2 mm) and left coronary artery differed significantly (2 to 7.3 mm; p <0.001). Conclusion: From the results, it was evident that the diameter of left coronary artery was larger than right coronary artery in majority of CAGs.