Objective: To explore the three dimensional distribution of the target sites of right ventricular outflow tract idiopathic ventricular arrhythmia(RVOT-PVC/VT). Methods:Sixty consecutive patients were included in the study. The target sites were identified as the earliest activation point by non-contact mapping, and were confirmed by successful ablation. The distribution of the target sites was observed in three dimensional geometry of RVOT. Results:Catheter ablation was successful in 49 patients whose target sites were located below the pulmonary valve. Among them,the target sites were located in the superior area in 15 patients, the inferior area in 34 patients, the anterior area in 30 patients, the posterior area in 19 patients, the free wall in 17 patients and the septum in 32 patients respectively. Catheter ablation was successful in 9 of 11 patients whose target sites were located above the pulmonary valve. Conclusion:Non-contact mapping could be helpful for identification the catheter ablation target sites of RVOT-PVC/VT.