Abstract: A method of producing silica-coated metal nanoparticles with at least one tetraalkoxysilane, from nanoparticles, referred to as metal nanoparticles, includes a quantity of at least one metal of zero oxidation state, a quantity of a catalytic hydrolysis composition, a quantity of liquid solvent medium and a quantity of water, so as to obtain a hydrolysis/condensation enabling the metal nanoparticles to be coated with silica, wherein the liquid solvent medium consists of at least one solvent chosen from the group formed by non-alcoholic organic solvents.