Abstract: Background: Various biomarkers and clinical variables are used to determine the probability risk, diagnosis, and the prognosis of acute ischemic stroke, but effective markers are still warranted.Aim: We aimed to determine the effectiveness of Hs-cTnI levels to predict the prognosis of AIS.Methods: This study was planned as a retrospective observational study. Patients with available data and over 18 years old were included in the study. Diffusion magnetic resonance images were evaluated by a senior radiologist and the infarct size was calculated.Results: We included 110 (54.2%) males and 93 (45.8%) females; a total of 203 patients with a mean age of 68.9 were included in the present study. Patients were divided into two groups according to the cut-off level of Hs-troponin-I (group I: lower than 8.5 mg/dL; group 2: higher than 8.5 mg/dL). These two groups were compared for mortality and infarct volume. Infarct volume and the mortality ratio of the group 2 was significantly higher [p = 0.041, U = 4294.5, LV = 6.5 (IQR = 1.8–25.4)].Conclusions: Hs-troponin I may be an effective biomarker in predicting the prognosis of patients with acute ischemic stroke. Multicenter comprehensive prospective studies are warranted to obtain stronger results.