A method of manufacturing a surface acoustic wave device formed in one chip and including over a semiconductor substrate at least an IC region and a surface acoustic wave element region that are horizontally disposed, the method including: forming in the IC region over the semiconductor substrate a semiconductor element layer that includes a semiconductor element and an insulation layer covering the semiconductor element and being deposited also in the surface acoustic wave element region; forming over the semiconductor element layer a wire layer that includes a plurality of wires coupled to the semiconductor element and a wire insulating film deposited over the plurality of wires to provide insulation among the wires, the wire insulating film being deposited also over the insulation layer in the surface acoustic wave element region; forming an interlayer insulating film having a flattened surface on the wire insulating film in the IC region and the surface acoustic wave element region; forming a piezoelectric thin film on the interlayer insulating film; and forming a surface acoustic wave element on the piezoelectric thin film in the surface acoustic wave element region.