An information processing apparatus according to the present invention is configured to project a given region (e.g., region of interest or lesion of interest) in a three-dimensional image (e.g., MRI image or X-ray CT image) onto a plane including a two-dimensional image (e.g., ultrasonic image) of an object, and cause a display unit to display an error range caused by projection (range where a corresponding region of the region of interest in the two-dimensional image may exist, also referred to as a search range) including the projected region in such a manner that the error range is overlaid on top of the two-dimensional image.Therefore, a user is able to efficiently search for the corresponding region in the two-dimensional image which corresponds to the region of interest in the three-dimensional image.