1. A medical information-display apparatus comprising: a display unit that displays a main examination area for displaying a thumbnail of a medical image to be read, and an observation-image preparation area for displaying a thumbnail of a medical image selected as a medical image to be used for image reading; and a display control unit that controls a display of medical information onto the display unit, wherein the display control unit causes the display unit to display in the main examination area a thumbnail of a medical image to be read, when receiving an operation of displaying in the observation-image preparation area the medical image of which thumbnail is displayed in the main examination area, the display control unit specifies a medical image to be a comparison subject based on attribution information about the medical image of displayed thumbnail, and causes the display unit to display a thumbnail of specified medical image.