PROBLEM TO BE SOLVED: To provide an image processing device which can improve the clarity of tumor tissue in a virtual diffusion weighted image.SOLUTION: An image processing device includes an image acquisition unit that acquires a first diffusion weighted image captured using a first b value a setting unit that sets a first cut-off diffusion coefficient having a second b value, and 0 or more value an image deriving unit that derives a virtual diffusion weighted image in the second b value, in a pixel in which a diffusion coefficient corresponding to a pixel of the first diffusion weighted image is larger than the first cut-off diffusion coefficient, on the basis of the diffusion coefficient and the first diffusion weighted image and a display unit that displays the virtual diffusion weighted image.COPYRIGHT: (C)2016,JPO&INPIT