Colloidal silver dispersion and silver nanoparticles were prepared by ethanol reduction of silver ions with Flavonoid as a stabilizer. Colloidal stability is achieved by adsorption of the Flavonoid molecules onto the particles. The size and optical properties of the obtained colloids are influenced by the Flavonoid molecule nature attached to the particle surface. Depending on the nature of the Flavonoid molecules attached to the particle surface, the size of the silver particles are lays between 2 to 250 nm rangers. The reduction process of Ag(+) ions in ethanol leads to stable dispersions of silver colloid. It is estimated that the Flavonoid molecules work both as a stabilizer and as a reduction booster. When the Flavonoid molar ratio (R) in monomer units to Ag metal is too low or high, the stability of the colloid become unstable and the particles are aggregated. At certain molar ratio of Flavonoid, however, very stable and very fine colloidal silver particle (ranged to a few nanometer) are obtained, which size is much smaller than when N-vinyl-2-pyrrolidone (PVP) is used as a stabilizer.