Fusariosis are very widespread in common winter wheat, of which rot of the root, the base of the stem and the grains meet with the highest frequency. Vegetable compounds with antifungal activity are important factors in the integrated protection system and, at the same time, ecologically harmless. Establishing of the protective capacity of the oxidized tannin extract, isolated from commercial black tea against the Fusarium avenaceum and F. oxysporum fungi, that are very widespread in common winter wheat under the conditions of the Republic of Moldova. The commercial black tea extract (RISTON®, Ceylon black leaf tea, Sri Lanka) was obtained by static method of mechanical agitation (maceration and draining, carried out in three stages of 24 hours each) with subsequent concentration by distillation and drying at a temperature of 45oC to a constant mass. The evaluation of the antioxidant activity of the tea extract was carried out with the application of the ABTS (2,2 azinobis 3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (2,2 diphenyl-1-picryl hydrazyl) tests. To determine the total content (Ctotal) of acid functional groups (carboxylic and phenolic), the Boehm method, partially modified, was used. Wheat grains (2 genotypes – Moldova 16, L Selania/Accent) were treated for 4 hours with an aqueous solution of oxidized black tea, dried in the open air for 24 hours and then kept in F. avenaceum, F. oxysporum culture filtrates for 18 hours. It was shown that when applying concentrations of 0,0025 and 0,005% tannin extracts, stimulation of germination, radicle and stem growth of common wheat occurred, which led to an increase in vigor index by 5,4-47,8% and dried mass per plant by 5,0-35% in relation to culture filtrates, respectively. The obtained data demonstrate the identification of a new protector of common wheat, ecologically pure – black tea tannin extract against the causative agents of root rot.