Background and Objective: RFCA is generally accepted to treat PSVT (AVNRT and AVRT) in adult. As the aging society is gone fast in Korea, palpitation is complained by elderly patient that is sometimes diagnosed as PSVT( paroxysmal supraventricular tachycardia: AVNRT and AVRT ). However elderly patient prefer conservative treatment after emergency management due to age, economic problem and negative attitude of life and then complication may be more frequently occured by tachycardia to compare younger patient because of underlying disease and older age. We performed this study to evaluate the efficiency and safety of RFCA (radi ofrequency catheter ablation) to cure AVNRT( atrioventricular nodal reentrant tachycardia and AVRT( atrioventricular reentrant tachycardia ) in elderly patIents. Methods: The study patients were AVNRT or AVRT who were managed by RFCA from January 2000 to December 2004. They were diagnosed as PSVT by 12 lead ECG before RFCA. The study patients were divided as two groups that were group 1 ( nonelderly group; 16-64 years) and group 2 (elderly group: over 65 years). Clinical characteristics and RFCA result were compared between two groups. Results: The study number are 182. Number of nonelderly is 165 (90.7%) and mean age is 41.1짹13.1 years (16-64). Number of elderly is 17 (9.3%) and mean age is 70.4짹4.7 years (65-81) (p<0.001). Underlying disease as DM (diabetes mellitus) or HT (hypertension) is higher in elderly group. (nonelderly, 15.8%:elderly,100.0%) (p<0.001). Tachycardia complication as heart failure is higher in elderly group than nonelderly group (nonelderly, 0 % : elderly, 5.9 %) (p=0.002). There are no statistical difference in RFCA result as procedure complication, recurrence, procedure time, fluoscopy time and cumulative ablation time between two groups. Conclusion: RFCA is recommended for first treatment modality of AVNRT and AVRT in elderly patient as like nonelderly group even though more large study is needed to confirm safety and efficiency of RFCA in elderly person.