An image processing apparatus according to an embodiment includes a processing circuitry. The processing circuitry obtains an MR image acquired by a magnetic resonance imaging apparatus and related to a brain. The processing circuitry divides a region of the brain in the MR image, into plural regions. The processing circuitry sets a parameter value used in generation of a calculated image generated by synthetic MRI and related to the brain, such that a relation of contrast among regions included in the plural regions becomes a predetermined relation. The processing circuitry generates the calculated image by the synthetic MRI, by using the MR image and the parameter value.