Although pericardial fat volume (PFV) has been suggested to be associated with atrial fibrillation (AF), only a few studies have reported the association between pericardial fat and clinical outcome after radiofrequency catheter ablation (RFCA). The purpose of this study was to explore the factors associated with PFV and its prognostic significance after catheter ablation for AF, depending on the types of AF.We included 665 patients (76.7% male, 57.3±11.1years of age, 67.7% with paroxysmal AF [PAF] and 32.3% with persistent AF [PeAF]) who underwent RFCA for AF, and compared PFV with clinical variables. The factors associated with clinical recurrence of AF were evaluated.1. PFV (10cm3) was independently correlated with age (B=0.09, 95% CI 0.06–0.13, p<0.001), body mass index (BMI) (B=0.25, 95% CI 0.12–0.38, p<0.001), body surface area (BSA) (B=10.51, 95% CI 7.64–13.39, p<0.001), and left atrial (LA) dimension (B=0.09, 95% CI 0.03–0.14, p=0.003). 2. During the 19.3±8.5month follow-up period, the clinical recurrence rate was 26.5%. PFV (HR 1.06; 95% CI 1.02–1.10, p= 0.004) and PeAF (HR 1.86; 95% CI 1.31–2.62, p<0.001) were independent predictors of clinical recurrence after RFCA. 3. PFV was significantly greater in PeAF patients with recurrence compared to those without (p=0.001), but, not in the PAF group (p=0.212). 4. PFV was independently associated with post-ablation recurrence only in PeAF (HR 1.10; 95% CI 1.05–1.16, p<0.001).PFV was independently associated with old age, greater LA dimension, and high BMI and BSA, and a significant predictor for AF recurrence after catheter ablation for PeAF.