The aim of the research – to study the Mexidol (ethylmethylhydroxypyridine succinate) effect on the factor induced by hypoxia (HIF-1α) expression in the frontal cortex of the brain in its ischemia. Material and methods. The work was performed on the 64 male Wistar rats. The expression of HIF-1α was determined immunohistochemically. Results and discussion. It is determined that single intraperitoneal administration of Mexidol at a dose 120 mg/kg and oral administration at a dose 100 mg/kg three times a day for 14 days is not affected the expression of HIF-1α. Unilateral occlusion of the common carotid artery increases the expression of HIF-1α at 4 hours after the occlusion. Oral administration of Mexidol at a dose 100 mg/kg three times a day for 14 days before and after ischemia increases the expression of HIF-1α after 4 and 12 hours in comparison with the norm, on the 5th day in comparison with occlusion control. Thus, it has been established that Mexidol increases the expression of HIF-1α in the frontal cortex of rat brain not under normal conditions, but in unilateral occlusion of the common carotid artery.