PROBLEM TO BE SOLVED: To calculate the physical quantities of a plurality of types of base materials without increasing the computation time.SOLUTION: An image processing device includes: a first base material conversion unit which respectively calculates the physical quantities of two or more base materials contained in the first base material group on the basis of the two or more types of projection data having the different energy distributions； an image generation unit which generates at least one of the projection image and restructured image of the subject and the plurality of images from the physical quantities of the two or more base materials contained in the first base material group； and a second base material conversion unit which calculates the physical quantity of the base material contained in the second base material group different from the first base material group on the basis of the plurality of images.SELECTED DRAWING: Figure 2【課題】 演算時間を増大させることなく複数種類の基底物質の物理量を算出する。【解決手段】 エネルギー分布の異なる２種類以上の投影データに基づいて、第１の基底物質群に含まれる２以上の基底物質の物理量をそれぞれ算出する第１の基底物質変換部と、前記第１の基底物質群に含まれる２以上の基底物質の物理量から、被写体の投影像又は再構成像の少なくとも一方であって、かつ、複数の画像を生成する画像生成部と、複数の前記画像に基づいて、前記第１の基底物質群とは異なる第２の基底物質群に含まれる基底物質の物理量を算出する第２の基底物質変換部と、を備える画像処理装置を提供する。【選択図】図２
