A film forming method includes: placing a substrate on which a pattern, which includes a plurality of convex and concave portions, is formed on a stage disposed inside a chamber; and selectively forming a silicon-containing film on the plurality of convex portions of the pattern by applying a bias power to the stage and introducing microwaves into the chamber while supplying a processing gas containing a silicon-containing gas and a nitrogen-containing gas into the chamber to generate plasma, wherein the selectively forming the silicon-containing film includes a first film formation of forming a silicon-containing film around upper sides of the plurality of convex portions and a second film formation of forming a silicon-containing film on upper portions of the plurality of convex portions.