The oxidative stress associated with ischemic stroke is a major factor damaging the nervous tissue. Thyroid hormones have a significant effect on the body’s redox status, however, the impact of their derivatives, thyronamines, considered as potential neuroprotectors, on the characteristics of lipid peroxidation (LP) is not clearly understood. The study was aimed to assess the impact of the Т0АМ thyronamine synthetic analogue on the main LP indicators in the model of acute cerebral ischemia. Permanent ligation of the right common carotid artery was performed to simulate acute cerebral ischemia in white rats. The animals were divided into two groups: the control group receiving no treatment and the experimental group, to which the Т0АМ thyronamine synthetic analogue was intraperitoneally administrated (75 mg/kg of the rat’s body weight). After 24 h the rat was decapitated, and the cerebral cortex tissue was extracted for biochemical analysis. The following LP indicators were determined by spectrophotometry: malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx). When administering the Т0АМ thyronamine synthetic analogue, a significant (2-fold) decrease in MDA levels was observed in the ischemic hemisphere (р = 0.022), along with the 2.49-fold increase in the GPx activity in the brain tissue (р = 0.004) of the intact hemisphere and the 2.65-fold increase in its activity (р = 0.021) in the ischemic hemisphere, as well as the 1.23-fold increase in SOD activity in the ischemic hemisphere (р = 0.042). The Т0АМ thyronamine synthetic analogue has a great potential in terms of activation of the antioxidant protection mechanisms in the cerebral cortex of white laboratory rats under conditions of acute hemispheric ischemia.