This radiation-therapy simulation apparatus is provided with a calculation unit, a correction unit, and a storage unit. The calculation unit calculates, in advance, for a plurality of irradiation conditions, the radiation-dose distributions when a standard model of the human body is irradiated with particles. The storage unit stores data related to the radiation-dose distributions. An operator inputs, into the radiation-therapy simulation apparatus, irradiation conditions and patient-body-type information. The correction unit calculates a conversion matrix indicating the conversion required to match body-type information related to the standard model of the human body, with the patient-body-type information. The correction unit extracts, from the storage unit, data related to the radiation-dose distribution calculated under irradiation conditions corresponding to the inputted irradiation conditions. The correction unit calculates a corrected radiation-dose distribution by converting the radiation-dose distribution in accordance with the conversion matrix. According to this radiation-therapy simulation apparatus, an increase in calculation time is inhibited.本發明提供一種能夠抑制計算時間延長之放射線治療模擬裝置。本發明的放射線治療模擬裝置對基於照射於患者的目標部位之放射線之劑量分佈進行運算,該放射線治療模擬裝置構成為,具備:記憶部,關於複數個照射條件,記憶對既定體型的人體模型照射放射線時的各劑量分佈的資料;輸入部,輸入適用於對患者照射放射線時之照射條件以及患者的體型資訊;及修正部,根據患者的體型資訊以及人體模型的體型資訊,對記憶於記憶部之劑量分佈的資料進行修正。
