Atrial fibrillation (AF) coexists with left ventricular diastolic dysfunction (LVDD), but the impact of catheter ablation across LVDD stages is unclear. The study aimed to quantify AF ablation effects on left ventricular diastolic function, remodeling, and rhythm outcomes across the LVDD spectrum. We studied 182 patients undergoing AF ablation, classified as no LVDD (Group A), grade 1 LVDD (Group B), or grades 2 to 3 LVDD (Group C). Echocardiography was performed at baseline and 1, 3, 6, and 12 months to assess diastolic indices and remodeling. Changes were evaluated with generalized estimating equations, and a 6-month landmark analysis related LVDD trajectories to AF recurrence. Group C showed sustained reductions in LVDD grade and E/e' with progressive left atrial reverse remodeling and early improvement in concentric remodeling. Group B demonstrated increased e' and E/A with later improvement in concentric remodeling but no consistent downgrading of LVDD. In Group A, LVDD grade rose, then regressed by 12 months and remained below grade 1. AF recurrence did not differ among groups, but in Group C, sustained LVDD improvement was associated with lower recurrence after ablation. In conclusion, AF ablation exerts stage-dependent effects on left ventricular diastolic function and remodeling; advanced LVDD confers the greatest benefit and may represent an expanded indication rather than a contraindication for ablation, and incorporating LVDD stage and its evolution into evaluation may refine prognosis and follow-up.