Crystallization of stable polymorphs of glycine was carried out from aqueous solution in the presence of novel metal nanaoparticles. Even lower concentration of novel metal nanaoparticles yield α and γ mixed nucleation. When the silver nanoparicles volume concentration reached 10%, the solution yield γ nucleation totally. The UV-vis spectra and Raman spectra have proved that glycine interact with the negative silver with amino cation. The interaction effectively prevent the formation of glycine alpha crystal type double-layer structure, thus inhibiting the formation of alpha crystal form, promotes the formation of gamma crystalline.