With respect to a film deposition method of depositing a silicon nitride film doped with a desired metal on a substrate, the film deposition method includes (a) supplying a silicon-containing gas into a processing chamber in which the substrate is accommodated, (b) supplying a metal-containing gas into the processing chamber, the metal-containing gas containing the desired metal, (c) supplying a nitrogen-containing gas into the processing chamber, after performing (a) at least once and performing (b) at least once.