Provided is a method of manufacturing a conductive metal thin film, the method including: a) heating and stirring a first solution containing a metal precursor, acid, amine, and a reducing agent to synthesize metal nano-particles on which formation of a surface oxide film is suppressed; b) dispersing the metal nano-particles synthesize in step a) in a non-aqueous solvent to prepare a conductive ink composition; c) applying the conductive ink composition onto an insulating substrate; and d) heat-treating the insulating substrate applied with the ink composition to form a conductive metal thin film. With the method of manufacturing a conductive metal thin film according to the present invention, large area conductive thin film may be manufactured as compared with the existing conductive ink composition based on noble metal nano-particles. In addition, the conductive metal thin film having excellent conductivity may be manufactured by suppressing a surface oxide film from being formed.