A cleaning method for a film-forming apparatus is provided. The film-forming apparatus includes a film-forming-raw-material-gas supply source, a film-forming-reaction-gas supply source, a first-cleaning-gas supply source, a second-cleaning-gas supply source, a stage provided in a processing chamber and configured to receive a substrate and to be elevatable, and a cap member provided in the processing chamber and facing the stage to form a processing space. The cleaning method includes forming a film over a substrate by supplying, to the processing space, a film-forming raw material gas from the film-forming-raw-material-gas supply source and a film-forming reaction gas from the film-forming-reaction-gas supply source; and cleaning an interior of the processing space by transferring the substrate out after the formation of the film, and supplying, to the processing space, a first cleaning gas from the first-cleaning-gas supply source and a second cleaning gas from the second-cleaning-gas supply source, in an alternating manner.