Background: Supraventricular tachycardia (SVT) is a common arrhythmia with associated symptoms such as palpitation, dizziness, and fatigue. It significantly affects patients’ quality of life (QoL). Radiofrequency cardiac ablation (RFCA) is a highly effective treatment to eliminate arrhythmia and improve patients’ QoL. The purpose of this study was to assess the level of QoL among patients with SVT and examine the difference in QoL before and after RFCA. Methods: One group pre-posttest design with a convenience sample of 112 patients was used. QoL was assessed by 36-Item Short Form (SF-36). Data were collected at admission through face-to-face interviews and 1-month post-discharge through phone interviews. Results: There was a significant difference between QoL before (33.7±17.0) and one month after (62.5±18.5) the RFCA. Post-RFCA patients diagnosed with atrioventricular re-entry tachycardia had higher QoL than other types of SVT. Moreover, there were significant negative relationships between QoL and the number and duration of episodes pre- and post-RFCA. There were no significant differences in QoL based on: age, sex, working status, marital status, smoking, coronary artery disease, diabetes mellitus, and hypertension. Conclusions: After RFCA, the QoL of patients with ST improved for both physical and mental component subscales.