PROBLEM TO BE SOLVED: To provide a cyclotron-type accelerator and a particle beam irradiation device comprising the same, and a beam extraction method, capable of successively extracting a predetermined energy beam at predetermined timing.SOLUTION: A cyclotron-type accelerator comprises: an annular coil 13; two main electromagnets, installed so as to face each other, for forming a magnetic field therebetween; high frequency acceleration cavities 21, 22 and a dee electrode for accelerating a beam; a beam extraction path 140 for extracting the beam to the outside; and a beam desorption device composed of built-in coils 28, 28A that are disposed in the dee electrode and generate deflection magnetic fields, at a plurality of positions in a radial direction of the coil 13, for desorbing the beam from a beam orbit and guiding the beam to the beam extraction path 140.SELECTED DRAWING: Figure 3COPYRIGHT: (C)2020,JPO&INPIT【課題】所定エネルギービームを所定タイミングで連続的に取出すことができるサイクロトロン型加速器、とそれを備えた粒子線照射装置、ならびにビームの取出し方法を提供する。【解決手段】環状のコイル13と、互いに対向して設置された、その間に磁場を形成する2つの主電磁石と、ビームを加速する高周波加速空洞21,22およびディー電極と、ビームを外部に取り出すビーム取出し経路140と、ディー電極内に配置され、コイル13の半径方向の複数の位置でビームをビーム周回軌道から離脱させてビーム取出し経路140へ導くための偏向磁場を発生させる内蔵コイル28,28Aからなるビーム離脱装置と、を備えたサイクロトロン型加速器。【選択図】図3