Paroxysmal atrial fibrillation (PAF) can originate from thoracic veins, i.e. pulmonary veins(PV), superior vena cava(SVC), ligament of Marshall, and left-sided SVC. Isolated anomalous pulmonary venous return not associated with atrial septal defect is a rare congenital anomaly. We report a case of PAF originating from anomalous right superior pulmonary vein(RSPV), in whom PAF was treated by RF ablation without recurrence. A 59-year-old man with drug refractory paroxysmal atrial fibrillation was referred for radiofrequency catheter isolation of pulmonary vein. Intracardiac thrombi and shunt were excluded by transesophageal echocardiography. Multi-slice computed tomography demonstrated anomalous dainage of RSPV into SVC. He underwent EP study and PV isolation in postabsorptive, unsedated state. After transseptal catheterization was performed, selective PV angiograms were performed. Selective pulmonary venogram showed normal anatomy of left PVs, small right middle PV and right inferior PV. RSPV draining into SVC was confirmed by angiograpy. Segmental ostial isolation of PV was performed during AF. Isolation of left superior PV did not terminated AF. Immediate recurrence of AF was noted after DC cardioversion(DCCV) with earliest endocardial activation at RSPV. AF recurred repetitively immediately after DCCV with earliest endocardial activation at RSPV. Isolation of RSPV from SVC terminated AF without further recurrence of AF. SVC was completely isolated from RA , and confirmed using 25-mm Lasso catheter. Transient right diaphragmatic paresis was observed upon RF energy delivery to junction between RA and SVC. To avoid permanent damage to right phrenic nerve, low energy (10-Watts) RF pulses were delivered areas where local capture of phrenic nerve did not occur. Segmental ostial isolation was performed sequentially in 2 left PVs and right inferior PV. There was no conduction recurrence in 4 PVs and SVC. Post RF PV angiograms and follow-up CT scan showed no stenosis in all PVs and SVC. He is free of AF symptom without use of antiarrhythmic drug 9 months after PV isolation. Anomalous origin of PV can be a focal source of AF, and RF isolation of the PV could be curative treatment for this condition.