Abstract: Tetrapeptide L-alanyl-L-glutamyl-L-aspartyl-glycine (SEQ ID NO: 1) of the general formula L-Ala-L-Glu-L-Asp-Gly (SEQ ID NO: 1) is proposed as a biologically active compound with a geroprotective effect. The use of L-Ala-L-Glu-L-Asp-Gly (SEQ ID NO: 1) tetrapeptide in medicine is proposed for preparing a substance displaying a geroprotective effect. There is proposed a pharmacological substance, which contains as its active base an effective amount of tetrapeptide of the formula L-alanyl-L-glutamyl-L-aspartyl-glycine (L-Ala-L-Glu-L-Asp-Gly) (SEQ ID NO: 1) or its salts of the amino group (acetate, hydrochloride, oxalate) and of carboxyl groups (the salts of metals-Sodium, Potassium, Calcium, Lithium, Zinc, Magnesium, and also the salts of organic and inorganic cations-ammonium and triethylammonium). The substance is proposed for parenteral, intranasal, oral administration, and local application.