An image processing apparatus according to an embodiment includes an acquiring unit, a correcting unit, and a perfusion image creating unit. The acquiring unit obtains a pixel value of a myocardium tissue and an arterial blood before a contrast agent injected in a second contrast examination arrives at a cardiac of a subject when myocardium perfusion data is created, by performing the second contrast examination that captures a second medical image group including the cardiac of the subject who is given an injection of a contrast agent again after a first contrast examination that captures a first medical image group. The correcting unit corrects contrast agent concentrations of an arterial blood and a myocardium tissue in the second medical image group using acquired each pixel value. The perfusion image creating unit computes the myocardium perfusion data in the second contrast examination based on the corrected contrast agent concentrations.
