A film deposition method using a film deposition apparatus, includes: a film deposition process step in which at least a substrate is mounted on at least one of the circular concave portions and a film is deposited on the substrate; and a particle reducing process step performed before or after the film deposition process step, in which particles in the vacuum chamber are reduced without mounting substrates on the circular concave portions, the particle reducing process step including, a step of supplying a first gas to the vacuum chamber; a step of generating plasma from the first gas by supplying high frequency waves to a plasma generating device provided for the vacuum chamber; and a step of exposing the plurality of circular concave portions, on each of which a substrate is not mounted, to the plasma while rotating the susceptor.