Arterial switch operation (ASO) is considered the procedure of choice for transposition of great arteries (TGA). The results and long-term prognosis improved with recent advances in perioperative management. We herein analyze the clinical outcome of patients undergoing ASO at our institution during the past 3 years. From 2000 to 2002, 44 patients (30 male and 14 female) of TGA received ASO. Age at operation varied from 4 days to 6.6 years (median 14 days) with body weight ranged from 2.25 kg to 18.1 kg (median 3.3 kg). Palliative procedure prior to ASO was performed in 8 patients (18.8%). Normal coronary artery pattern was found in 28 patients (63.6%). The early mortality was 11% (5/44). Only associated ventricular septal defect (VSD) was a significant predictor for operative mortality (p=0.012). With a follow-up ranged from 11 to 44 months, the gradient of neo-pulmonary artery stenosis was 16.5 +/- 18.2 mmHg. Four patients (10%) received balloon dilatation and the other three (7.7%) underwent reoperation. The gradient of neo-aortic stenosis was 16.5 +/- 18.2 mmHg that needed to be dilated in three patients (7.7%). The probability free from reintervention was 73% at the 3rd postoperative year. One patient had moderate degree of pulmonary valve regurgitation and six had moderate neo-aortic valve regurgitation. In conclusion, the ASO can be performed in infants with satisfactory results, even in those with a body weight less than 2.5 kg. Only associated VSD was shown to be a risk factor.