FIELD : agriculture; medicine; veterinary science; pharmaceutics.SUBSTANCE : invention relates to agriculture, medicine, veterinary science and pharmaceutical industry. Method of increasing antibacterial properties of silver nanoparticles involves treatment with UV radiation at power of 40 W and wavelength λ= 254 nm of preparation of silver nanoparticles with size of 70?±?0.5 nm in the concentration range of 0.1–0.05 M during 1–5 minutes.EFFECT : disclosed is a method of increasing antibacterial properties of silver nanoparticles.1 cl, 2 tbl, 1 dwg