In an image creating device, an obtainer obtains the phase of a magnetic resonance signal generated from a target object upon application of a static magnetic field and a high-frequency magnetic field to the target object (step S102). A calculator calculates a change level of the obtained phase per a predetermined distance in a direction of the static magnetic field (step S103). A generator generates an image representing a positional distribution of a parameter depending on the calculated change level (step S106).