Actinomycetes are widespread in the nature. The basic environment of their dwelling is the soil, there are actinomycetes and in layers of sea and fresh water. Actinomycetes are active producers of various physiologically active substances: vitamins, hormones, enzymes, amino acids, lipids, etc. Also actinomycetes, in particular, genus Streptomyces, are the basic producers of the antibiotics made by pharmaceutical industry. Antibiotics of a microbial origin are widely applied in medicine, veterinary science, and also in protection of plants. Perceptivity of their using is connected with rather weak toxicity for the people and animals in comparison with chemical protection frames, specificity of action, ability to get into tissues of plants and high activity against activators of illnesses. In plant growing, actinomycetes which synthesized metabolites are used as herbicides, insecticides, plant growth-stimulators. Object of research was strain Streptomyces fradiae 19, isolated from the soil of the Central Part of Moldova. Antimicrobial activity was defined by using the method of agar blocks. Test cultures were phytopathogenic fungi: А alternata, А. niger, B. cinerea, F. oxysporum, F. solani, and phytopathogenic bacteria – A. tumefaciens, X. campestris. Phytopathogenic fungi grew up on a agar wort of 5.0°Blg, phytopathogenic bacteria – on a potato agar. For X. campestris – the agent of vascular cabbage bacteriosis, metabolites of the investigated strain has caused formation of inhibition growth zones to 32.0 mm. Growth of Alt. alternata, causing so-called olive mould of rice or black spot, and in aggregate with other phytopathogenic fungi – Cl. herbarum, E. purpurascens, B. cinerea – dark mildew of an wheat ear, was inhibited by substances of strain S. fradiae 19 to 13.0 mm in diameter, and at Asp. niger – to 10.5 mm. Antimicrobial action against B. cinerea, causing clamp rot of a sugar beet, also has been observed (a zone in diameter of 11.5 mm). For F. oxysporum – the agent of cotton wilt, diameter of inhibition growth zones has made 13.5 mm. Antimicrobial activity against phytopathogenic fungus F. solani, causing rot of a soya beans, was found out. For this test culture diameter of suppression growth zone formed about 15.0 mm. On growth of phytopathogenic bacterium A. tumefaciens, which causes the fruit-bearing plants crown gall, investigated strain has not rendered any influence. Diameter of a zone of a growth inhibition of the phytopathogenic bacterium Cl. michiganensis, causing a bacterial cancer of tomatoes, revealed to 14.0 mm. Thus, the conducted researches show that strain Streptomyces fradiae 19, isolated from soils of Moldova, possesses antimicrobial activity in relation to a number of test microorganisms in different degree. In particular, antagonistic activity in relation to phytopathogenic microorganisms is maximum expressed against X. campestris, and also activity against F. solani, F. oxysporum and Cl. michiganensis is established.