Objective To evaluate the ability of the triglyceride-glucose (TyG) index and the brain symmetry index (BSI) to predict stroke recurrence in patients with acute ischemic stroke (AIS). Methods This retrospective study enrolled 366 AIS patients admitted to the Fourth Affiliated Hospital of Nanjing Medical University between January 2021 and August 2022. Before discharge, resting electroencephalography was recorded to obtain the eyes-open BSI (BSIo) and eyes-closed BSI (BSIc); the TyG index was calculated concurrently. Stroke recurrence was assessed at 3, 6, 12 and 18 months. Logistic regression and receiver-operating characteristic analyses were used to determine the predictive performance of baseline TyG index, BSIo and BSIc. Results Sixty-two patients (16.9%) experienced stroke recurrence within 18 months. Baseline TyG index, BSIo and BSIc were significantly higher in the recurrence group than those in the non-recurrence group (P<0.05). Multivariable logistic regression identified TyG index [odds ratio (OR)=2.273, 95% confidence interval (CI) (1.441, 3.585)] and BSIo [OR=27.305, 95%CI (1.155, 645.737)] as independent predictors of recurrence (P<0.05). TyG index and BSIo provided the highest predictive accuracy for recurrence within 3 months (area under the curve=0.777 and 0.795, respectively); their discriminative ability declined over longer follow-up periods. BSIo correlated positively with the National Institutes of Health Stroke Scale and modified Rankin Scale scores (P<0.001), and was elevated in patients with atrial fibrillation, heart failure or small-artery occlusion (P<0.05), while lowered in patients with diabetes (P<0.05). Conclusion Elevated TyG index and BSIo are closely associated with stroke recurrence after AIS and may serve as useful adjuncts for early risk stratification and individualized secondary prevention.