A particle beam irradiation apparatus which can perform high-precision beam irradiation position is obtained. The apparatus is provided with inverse mapping means having an inverse mapping mathematical expression model for generating an command value for the scanning electromagnet and an command value for kinetic energy of the charged particle beam from a desired irradiation position coordinate of the charged particle beam in an irradiation subject so that irradiation to the irradiation subject is implemented on the basis of the command values concerned, and the scanning electromagnet and the kinetic energy of the charged particle beam are controlled on the basis of the command values generated from the desired irradiation position coordinate of the charged particle beam in the irradiation subject by using the inverse mapping mathematical expression model, thereby irradiating the irradiation subject with the charged particle beam while scanning the charged particle beam.