Block copolymers: MOPEO-b-P??m and P??m-b-P??-b-P??m contained poly(ethylene oxide), its monomethyl ether and chemically complementary polyacrylamide were and used as special matrices in the borohydride reduction of Ag(+)ions. Ag-nanoparticles in the structure of compositions were obtained. The effect of chemical nature, molecular architecture and size stabilization of silver nanoparticles in bulk structure was shown.