Abstract: Disclosed are a solid state synthesis method of silver nanoparticles, and silver nanoparticles synthesized thereby. The method includes mixing a silver salt and a water soluble polymer acting as both a reducing agent and a protecting agent to produce a solid mixture, and milling the solid mixture by a high-speed vibration milling process to form silver nanoparticles within the water soluble polymer. According to the present invention, silver nanoparticles can be easily and simply produced in a solid state through high speed vibration milling, thereby reducing costs for industrial production and transportation of silver nanoparticles. In addition, the synthesized silver nanoparticles can be used for a long time since the silver nanoparticles are stable in a solid state for 1 year or more.