An apparatus and method for supporting computer aided diagnosis (CAD). The apparatus includes: a control processor configured to determine a duration during which a remaining image of a first region of interest (ROI) detected from a first image frame is displayed, based on a characteristic of measuring the first ROI; and a display configured to mark a remaining image of a second ROI of a second image frame in the first image frame and display the marked image on a screen, in response to the first image frame being acquired during a duration set to display the remaining image of the second ROI. the first image frame is obtained subsequent to the second image frame.