Background/aim: This study aimed to evaluate pulmonary vein (PV) anatomy using 256-slice computed tomography (CT), which may be necessary for electrophysiologists to know before radiofrequency catheter ablation (RFCA) therapy.Materials and methods: A total of 102 patients with paroxysmal and persistent atrial fibrillation underwent 256-slice cardiac CT angiography prior to catheter ablation. PV morphology, ostial diameter, ostial orientation, and distance from ostium to first bifurcation were evaluated using three-dimensional volume-rendering and multiplanar-reformatting technology. Results: We found that 72.5% of patients had four conventional PVs. On the right, 22.5% of patients had one accessory PV, 4.9% had 2 accessory PVs, 1% had one common PV, and 1% had one top vein. On the left, 27.5% of patients had one common PV. Additionally, 9.8% of patients had bilateral PV variation. Ostial size was larger for superior PVs than inferior PVs and larger for right PVs than left PVs. PV ostia on the right tended to be more circular. There was a rather wide variation of projective angle and distance from ostium to first bifurcation. Early branching occurred more often in the right inferior PV. Conclusion: 256-Slice CT can depict PV anatomy and afford substantial data, which will help electrophysiologists conduct the RFCA procedure safely and efficiently.