A magnetic resonance imaging device (100) according to an embodiment comprises a sequence control unit (120), an image generation unit (136) and a derivation unit (133b). The sequence control unit (120) performs, by controlling execution of a pulse sequence, a first imaging which collects data for a range that includes a target organ and a second imaging which collects data for a diagnostic image. The image generation unit (136) generates an image using the data collected by the first imaging. The derivation unit (133b) derives, on the basis of image processing using the image, an imaging region for which data for the diagnostic image is collected in the second imaging and a related region which is set related to the imaging region in the second imaging.