PROBLEM TO BE SOLVED: To obtain verification and recording of accurate irradiation of therapeutic radiation to an affected part while improving convergence of the therapeutic radiation in radiation therapy.SOLUTION: A treatment planning device comprises: a condition acquisition unit for acquiring treatment conditions including a position of an affected part, a necessary radiation dose to the affected part, and a limitation radiation dose to a part other than the affected part； a first planning unit for planning a first irradiation to emit radiation to a first irradiation field including a whole of the affected part； and a second planning unit for generating a treatment plan that satisfies the treatment conditions by a combination of the first irradiation planned by the first planning unit and radiation irradiation to an irradiation field including only a part of the affected part.【課題】放射線治療において、治療用放射線の集中性を高めつつ、治療用放射線が患部に正確に照射されていることの確認や記録を得られるようにする。【解決手段】治療計画装置が、患部の位置と、前記患部への必要線量と、前記患部以外の部位への限界線量とを含む治療条件を取得する条件取得部と、前記患部全体を含む第１照射野へ放射線を照射する第１照射を計画する第１計画部と、前記第１計画部が計画した前記第１照射と、前記患部の一部のみを含む照射野への放射線照射との組み合わせにて、前記治療条件を満たす治療計画を生成する第２計画部と、を具備する。【選択図】図２
