The silver nanoparticles of (4.18±0.5) nm in diameter were prepared using two-phase liquid-liquid method.-The size distribution and the stability of the silver nanoparticles were studied by the UV-vis spectrum.-The results showed that the silver colloid solution was stable and monodispersed.-The IR spectra indicated that the nanoparticles were capped by 1-nonanethiol.-Two-dimensional ordered structure of the nanoparticles was formed by self-assembly technique.