Aim: This study aimed to examine the relationship between short-term mortality and blood glucose values (BGV) obtained during the first week of ischemic stroke, when neurological causes, such as increased intracranial pressure, are mainly predominant in mortality prediction.Materials and Methods: This is a retrospective study that includes 417 patients with acute ischemic stroke (AIS), who were admitted to our hospital within the first 24 hours of the stroke. Data were recorded using the International Classification of Diseases Code. On the first, third, fifth, and seventh days of the stroke, the effect of BGV on the patient’s functional outcome was evaluated.Results: Of 417 patients, 90 (21.58%) died within a one-month follow-up period. There was no difference between the mortality and survival groups in terms of diabetes mellitus (DM) history (χ2=0.783; p=0.224). On the first, third, fifth, and seventh day of the stroke, BGV were significantly higher in the mortality group (130.5 mg/dL, 124.5 mg/dL, 133.5 mg/dL, and 132.5 mg/dL, respectively, according to the receiver operating characteristic analysis) than in the survival group (p<0.05). BGV of the fifth day (133.5 mg/dL) was an independent predictor for mortality (hazard ratio: 3.001; 95% confidence interval (1.43-6.3); p=0.004), while BGV of the other days were dependent on a coma scale.Conclusion: Hyperglycemia predicting short-term AIS mortality might be a DM-independent stress hyperglycemia. Although hyperglycemia is predominantly a coma-scale-dependent [modified Rankin Scale (mRS)] predictor during the first week of blood glucose monitoring, BGV of the fifth day may be an independent predictor of short-term mortality.