A production apparatus of composite silver nanoparticle including: a device for arranging a silver salt microparticle and at least an alcohol solvent selected from alcohols having a carbon number of 1 to 12; a raw material mixer for preparing an alcohol solution by mixing the silver salt microparticle into the alcohol solvent added more excessively than the mol number of the silver salt microparticle to make an excess alcohol solution; a reactor for generating a composite silver nanoparticle by heating the excess alcohol solution at a generation temperature PT generating an aldehyde for a generation time with a heater, in which a silver core is formed by reducing the silver salt microparticle by the alcohol solvent and/or the aldehyde and the composite silver nanoparticle having an organic coating layer originated from the alcohol solvent around the silver core is formed, and a chiller for cooling the alcohol solution.