Abstract Introduction Trimetazidine ameliorates myocardial ischemia via potentiating glucose oxidation. Whether such metabolic reprogramming protects against stroke risk in atrial fibrillation (AF) with ischemic heart disease (IHD) was unknown. Purpose To investigate the therapeutic impact of trimetazidine dihydrochloride on ischemic stroke in AF associated with IHD. Methods We collected data from a territory-wide clinical data registry (January 1999 to December 2020) with a coverage of 7.5 million population. 200,563 patients with IHD were identified. Amongst them, 13,092 (6.5%) had baseline AF (mean [SD] age: 79.7 [10.3] years, 44.8% female), and were identified as trimetazidine users (n=1,488) versus non-users (long-acting nitrates as control, n=11,604). Propensity matching at 1:1 was performed. Multivariable Cox regression was used to derive hazard ratios (HRs) for new-onset ischemic stroke. Result Over mean follow-up over 53.5 +/- 50.4 months, trimetazidine use was associated with a lower incidence of ischemic stroke (3.4% vs 7.6%, P<.001). Kaplan-Meier analyses showed trimetazidine use was associated with increased stroke-free survival period (Mean survival: 227.9 [4.9] versus 217.5 [3.6] months, Chi-square=39.0 P<.001). After adjusting for confounding factors, trimetazidine use remained an independent predictor of reduced ischemic stroke risk (adjusted HRs, 0.54, 95% CI, 0.37-0.78, P<.001). Conclusion Trimetazidine may reduce the risk of ischemic stroke in ischemic AF. These findings will need to be confirmed by randomized controlled trials.