To reduce a residual amount of chlorine atoms and oxygen atoms in a metal nitride film, and improve oxidation resistance of the metal nitride, film, in a temperature range of not deteriorating the characteristics of other film adjacent to the metal nitride film. A substrate processing apparatus is provided, comprising: a processing chamber into which a substrate is loaded, having thereon a substrate containing oxygen atoms, chlorine atoms, and metal atoms; a substrate support part for supporting and heating the substrate in the processing chamber; a gas supply part for supplying nitrogen atoms-containing gas and hydrogen atoms-containing gas into the processing chamber; a gas exhaust part for exhausting inside of the processing chamber; a plasma generation part for exciting the nitrogen atoms-containing gas and the hydrogen atoms-containing gas supplied into the processing chamber; and a control part for controlling the substrate support part, the gas supply part, and the plasma generation part.