An ultrasound diagnostic apparatus 1 using an index image display apparatus includes: index image display means 7 for displaying an ROI of an index image having a predetermined shape and to be superimposed on an image displayed on a monitor 5； a CPU 8 that is display form changing means that can change a display form of the ROI by a predetermined amount by one operation； an operation portion 4 for outputting an operation signal to the CPU 8； and an LCD panel 15 that is a change information display section including a plurality of operation buttons 15a to 15h provided in the operation portion 4 and representing graphic information that indicates an initial state of the ROI, and change information that is changed by the CPU 8.
