The present invention provides a method for producing metallic nanoparticles, which includes reacting a copper compound with a hydrazine reducing agent in an organic solvent in the presence of a precious metal compound, wherein the precious metal compound is a compound containing at least one precious metal selected from the group consisting of platinum, gold, silver, and palladium, and the total number of precious metal atoms in the precious metal compound is in the range of 1 to 10 at. % of the total copper atoms in the copper compound.