A silver complex is transformed into amphiphilic nanoparticles at room temperature using nanoreactors formedfrom an amphiphilic polyester. It takes a few minutes to form silver nanocolloids with a narrow particle size distribution.Developed silver forms a stable dispersion in both polar and nonpolar media. The amphiphilic polyester acts as areducing and stabilizing agent simultaneously. The size of the synthesized amphiphilic silver nanoparticles dependson the concentration of the invertible polyester and solvent polarity.