A marine display device , comprising: a detector means operable to detect a touch operation; an image acquirer means operable to acquire at least two of a navigation image containing map or nautical chart information created based on information obtained from a GNSS sensor for detecting a location of the display device, an underwater detection image created based on information obtained from an ultrasonic transducer for detecting underwater, and a radar image obtained from a radar antenna for detecting a location of an object around the display device; a display means operable to display acquired images in respective divided areas of a display screen; a gesture detector means operable to detect a predetermined touch gesture based on the touch operation detected by the detector; an operated location detector means operable to detect an operated location of the touch gesture; a divided area identifier means operable to identify which image among the images is displayed in the divided area corresponding to the operated location detected by the operated location detector; and an image processor means operable to have a function to perform scrolling or zooming of the display screen corresponding to the touch gesture, and for changing a direction or a motion range according to the image being displayed in the identified divided area, upon performing the scrolling or zooming; wherein the image processor means is adapted to perform the scrolling or zooming in a mode dependent on characteristics of the image identified by said divided area identifier means , and to apply a certain limitation to the image identified by said divided area identifier against the scrolling and zooming processing. a detector means operable to detect a touch operation; an image acquirer means operable to acquire at least two of a navigation image containing map or nautical chart information created based on information obtained from a GNSS sensor for detecting a location of the display device, an underwater detection image created based on information obtained from an ultrasonic transducer for detecting underwater, and a radar image obtained from a radar antenna for detecting a location of an object around the display device; a display means operable to display acquired images in respective divided areas of a display screen; a gesture detector means operable to detect a predetermined touch gesture based on the touch operation detected by the detector; an operated location detector means operable to detect an operated location of the touch gesture; a divided area identifier means operable to identify which image among the images is displayed in the divided area corresponding to the operated location detected by the operated location detector; and an image processor means operable to have a function to perform scrolling or zooming of the display screen corresponding to the touch gesture, and for changing a direction or a motion range according to the image being displayed in the identified divided area, upon performing the scrolling or zooming; wherein the image processor means is adapted to perform the scrolling or zooming in a mode dependent on characteristics of the image identified by said divided area identifier means , and to apply a certain limitation to the image identified by said divided area identifier against the scrolling and zooming processing. <EOS>