A method of manufacturing a semiconductor device includes: providing a substrate having an oxide film; performing, a predetermined number of times, a cycle of non-simultaneously performing supplying a precursor gas to the substrate, supplying a carbon-containing gas to the substrate, and supplying a nitrogen-containing gas to the substrate, or performing, a predetermined number of times, a cycle of non-simultaneously performing supplying a precursor gas to the substrate and supplying a gas containing carbon and nitrogen to the substrate, or performing, a predetermined number of times, a cycle of non-simultaneously performing supplying a precursor gas containing carbon to the substrate and supplying a nitrogen-containing gas to the substrate, the oxide film being used as an oxygen source to form a nitride layer containing oxygen and carbon as a seed layer; and forming a nitride film containing no oxygen and carbon as a first film on the seed layer.