The article discusses a method for producing silver nanoparticles (NPs) in aqueous solutions by reducing sodium borohydride in the presence of polyvinyl alcohol; selected optimal conditions for the synthesis. The resulting silver NPs have a spherical shape, with a diameter of from 30 to 130 nm. NPs are stable, do not precipitate and do not change color for 3–4 weeks. Electron microscopic images confirm the formation of a thin polymer film on the surface of cellulose fiber and show a change in the morphological surface of the treated samples compared to untreated ones. The energy dispersive microanalysis data showed that the raw cotton fabric contains C – 57.02%, O – 42.98%. After processing, nanoscale particles of silver are encapsulated on the surface of the fabric – 0.18–0.28%, which are distributed rather unevenly. Modification of cellulosic textile materials of silver NPs imparts a stable antimicrobial effect , as well as improves their physico-mechanical and hygienic properties. The air permeability indicators for cotton original fabric 180 dm3/m2×sec., For the treated composition based on polyvinyl alcohol, NaBH4, and silver nitrate – 175 dm3/m2×sec. The breaking load of the fabric is: for the initial – 311 N, for treated – within 320–360 N. The indicators of air permeability and strength characteristics of cotton fabric treated with the proposed composition comply with the regulatory requirements for this group of fabrics.