PROBLEM TO BE SOLVED: To provide a particle beam therapy system with improved expandability. A particle beam therapy system (1) has a building having a first floor (51) and second floors (53S, 53V), a particle beam generator (2) installed on the first floor to generate particle beams, and a particle beam generator (2). To the first irradiation device in the first treatment room from the first transportation system 3 (1) and the first transportation system branching from the first transportation system to the second floor to the second treatment room in the second treatment room. A particle beam therapy system comprising: a second transportation system 3 (2) for transporting a particle beam to an irradiation device, wherein the second transportation system is on a second floor different from the installation surface of the particle beam generator. The first deflection electromagnet 32 (2) for deflecting the particle beam in the direction is provided, the building 5 has a shielding wall 55 for shielding the first floor and the second floor, and the second transportation system is provided with the particle beam. It is provided behind the first bending electromagnet with respect to the traveling direction and penetrating the shielding wall. [Selection diagram] FIG.【課題】拡張性を向上させた粒子線治療システムを提供すること。【解決手段】粒子線治療システム１は、第１フロア５１と第２フロア５３Ｓ，５３Ｖと有する建屋と、第１フロアに設置され、粒子線を発生させる粒子線発生装置２と、粒子線発生装置から第１治療室内の第１照射装置へ粒子線を輸送するための第１輸送系３（１）と、第１輸送系から分岐して第２フロアを経由し、第２治療室の第２照射装置へ粒子線を輸送するための第２輸送系３（２）と、を備えた粒子線治療システムであって、第２輸送系は、粒子線発生装置の設置面と異なる第２フロアの方向へ粒子線を偏向させる第１偏向電磁石３２（２）を有し、建屋５は、第１フロアと第２フロアとを遮蔽する遮蔽壁５５を有し、第２輸送系は、粒子線の進行方向に対して第１偏向電磁石よりも後方で、遮蔽壁を貫通して設けられている。【選択図】図２
