The interest in herbal products capable of normalizing carbohydrate and lipid metabolism thus counteracting the “diseases of civilization” grows steadily. Biological activity of these preparations is often mediated by phenolic compounds. In this aspect, the raw material of European mountain ash (Sorbus aucuparia L.) has significant prospects, and its fruit are used in traditional medicine in diabetes.Aim. To obtain alcohol and ethyl acetate-alcohol extracts from European mountain ash leaves, study their phenolic composition by the HPLC method, determine the effect of the extracts on glucose metabolism in intact rats, as well as evaluate the effect of the most effective extract on lipid metabolism, uric acid metabolism, and the excretory renal function.Materials and methods. The alcohol soft extract (ASE, extractant – 50 % ethanol) and the ethyl acetate-alcohol soft extract (EAASE, extractant – a mixture of ethyl acetate and 96 % ethanol (8:2) after preliminary extraction of the raw material with chloroform) were obtained from leaves of European mountain ash. Using HPLC (Shimadzu LC20 Prominence chromatograph) the phenolic composition of the extracts was studied. The effect of the extracts (100, 250, 500 mg/kg intragastrically after single administration) on glycemia was determined in intact normoglycemic rats compared to the infusion of bilberry shoots (Vaccinium myrtillus L.) at a dose of 10 ml/kg (1:10). The effect of the extract, which showed the ability to reduce glycemia (ASE at a dose of 500 mg/kg for 6 days), on the content of glucose, uric acid, urea, creatinine, triglycerides and total cholesterol in the blood and on the excretory renal function under the conditions of water diuresis was also studied.Results. Chlorogenic acid, quercitrin (predominant in EAASE; 11.61 mg/g) and rutin (predominant in ASE; 3.57 mg/g), and in small amounts gallic, neochlorogenic and caffeic acids, catechin and hyperoside were identified in the extracts by HPLC. ASE after single administration at a dose of 250 and 500 mg/kg exerted a statistically significant hypoglycemic effect in normoglycemic rats, exceeding the effect of the infusion of bilberry shoots (10 ml/kg). The effect was also present after administration for 6 days at a dose of 500 mg/kg, which was characterized by the high level of safety, since it caused neither changes in the given indicators of lipid, nitrogen, purine metabolism, nor the shifts of indicators of the excretory renal function.Conclusions. The data obtained substantiate the expediency of further studies of the extracts from European mountain ash leaves for the development of new drugs or dietary supplements.