To the purpose of obtaining a particle beam irradiation apparatus to eliminate the influence of the hysteresis of the scanning electromagnet, to achieve beam irradiation with high accuracy. And an irradiation control unit 5 for controlling the scanning magnet 3 based on the target irradiation position coordinates Pi of the charged particle beam 1b and the measurement magnetic field Bs of the magnetic sensor 20 for measuring the magnetic field of the scanning electromagnet 3, measured by the magnetic field sensor 20 were. The inverse mapping means 22 for calculating a target magnetic field Bi from target irradiation position coordinates Pi of the charged particle beam 1b, irradiation control device 5, scanning be controlled to less than a predetermined threshold value the magnetic field error Be and measured magnetic field Bs and the target magnetic field Bi I had a compensator 23 for outputting a control input Io to the electromagnet 3.走査電磁石のヒステリシスの影響を排除し、高精度なビーム照射を実現する粒子線照射装置を得ることを目的とする。走査電磁石3の磁場を測定する磁場センサ20と、磁場センサ20により測定された測定磁場Bs及び荷電粒子ビーム1bの目標照射位置座標Piに基づいて走査電磁石3を制御する照射制御装置5とを備えた。照射制御装置5は、荷電粒子ビーム1bの目標照射位置座標Piから目標磁場Biを演算する逆写像手段22と、目標磁場Biと測定磁場Bsとの磁場誤差Beを所定の閾値以下に制御する走査電磁石3への制御入力Ioを出力する補償器23を有した。
