A screen synchronous control apparatus includes a reference timing transmitting unit 3 for transmitting a reference timing signal about display of a plurality of display screens 11, 12, and 13 at predetermined intervals, a display control unit 1 for transmitting a drawing instruction for displaying display data on the plurality of display screens 11, 12, and 13, and a plurality of display processing units 101, 201, and 301 each for receiving the drawing instruction transmitted from the display control unit 1, for executing the drawing instruction according to the reference timing signal transmitted from the reference timing transmitting unit 3, and for displaying the display data on the corresponding one of the display screens 11, 12, or 13.