The transradial approach for coronary angiography (CAG) is known to be associated with fewer vascular complications and shorter hospital stay than the transfemoral approach. In the transradial approach, the insertion of a guiding catheter can be affected by the shape and vascular tortuosity of the brachiocephalic and subclavian arteries. In this study, we compared the left transradial with the right transradial approach in elderly patients. From 1 July 2008 to 30 April 2009, we performed CAG and angioplasty in 143 cases via the left transradial approach (Group I) and in 219 cases via the right approach (Group II). Among elderly patients over the age of 65 years, Group I consisted of 63 cases (71.8±5.17 years, male: 55.6%) and Group II consisted of 97 cases (72.7±5.16 years, male: 52.6%). We evaluated the degree of axillary tortuosity, the angle of the aorta to the subclavian artery, the procedural success rate, the fluoroscopic times, the size of the radial artery, and the procedure-related complications of both groups. The degree of axillary artery tortuosity and the angle of the aorta to the subclavian artery increased with age. In elderly patients, the degree of axillary tortuosity in Group I tended to be less severe than that in Group II (good: 82% vs 67.7%, mild: 11.5% vs 17.2%, moderate: 3.3% vs 8.6%, severe: 3.3% vs 6.5%, p=0.059), and the angle of the aorta to the subclavian artery was smaller in Group I (small: 95.1% vs 83.9%, moderate: 3.3% vs. 5.4%, severe: 1.6% vs 10.8%, p=0.024). There was no statistical difference in the procedural success rate (96.8% vs. 89.7%, p=0.094), but the fluoroscopy time was significantly shorter in Group I (Group I: 46.8±26.4 sec, Group II: 58.2±36.6 sec, p=0.037). In elderly patients, the angle of the aorta to the subclavian artery was smaller and the fluoroscopy time was shorter via the left transradial approach compared with the right approach. We conclude that the left transradial approach is more effective and acceptable for elderly patients than the right approach.