['To determine whether the plasma level of free fatty acid (FFA) could be associated with recurrent stroke in cardioembolic (CE) stroke patients.', 'We analyzed data from 669 acute ischemic stroke patients and examined the association between FFA concentration and recurrent stroke in CE stroke patients compared with non-CE stroke patients.', 'The baseline plasma FFA concentration (mEq/L) was approximately 1.5-fold higher in CE stroke patients (1.01 ± 0.63) than in non-CE stroke patients (0.72 ± 0.51). Multivariate logistic analysis showed that an increased level of FFA was significantly associated with CE stroke (hazard ratio [HR] 2.124, confidence interval [CI] 1.492-3.024). During the mean follow-up period of 25.4 months, a total of 56 (8.4%) patients experienced a stroke recurrence. The recurrence rate did not differ between patients with CE (10.5%) and non-CE (8.0%) stroke (p = 0.396). In CE stroke patients, an elevated baseline FFA concentration was independently associated with stroke recurrence (HR 2.711, CI 1.056-6.959). However, there was no association between FFA and stroke recurrence in non-CE stroke patients.'] Is high free fatty acid level associated with recurrent stroke in cardioembolic stroke patients?