Purpose: Hyperhomocysteinemia in children can develop as a result of genetic defects, endocrine abnormalities or under the influence of dietary factors. An elevated level of homocysteine is considered a risk factor for the progression of chronic kidney disease. The aim of the work was to investigate the indicators of oxidative stress in the homogenate of the kidneys of immature rats in control and with hyperhomocysteinemia. Methods: The concentration of reduced and oxidized glutathione, the activity of superoxide dismutase, catalase and nitric oxide synthase were determined. The model of hyperhomocysteinemia was reproduced on one-month-old male rats, which were kept on a standard vivarium diet. The experimental group was intragastrically administered by D,L-thiolactone homocysteine hydrochloride in a 1% starch solution at a dose of 200 mg/kg of body weight 1 per day for 8 weeks. The corresponding volume of 1% starch solution was injected into the control group of animals. The activity of superoxide dismutase, catalase and nitric oxide synthase were determined spectrophotometrically. Concentration of reduced and oxidized glutathione by fluorometric method. Results: It was established that upon hyperhomocysteinemia the concentration of reduced glutathione, the activity of superoxide dismutase, catalase, and nitric oxide synthase was decreased against the background of an increase in the concentration of oxidized glutathione in the homogenate of the kidneys of immature rats. Conclusions: The obtained results indicate that in the kidneys of immature rats, the development of oxidative stress occurs in the direction characteristic of adult animals. The obtained results indicate that in the kidneys of immature rats the development of oxidative stress resembles the adult animals. The obtained results showed a decrease in the concentration of reduced glutathione and the activity of antioxidant defense enzymes which may indicate the development of pathological processes in the kidneys