According to one embodiment, this data display device has a display unit in which a rear support cover is mounted on the back surface of a rectangular display panel using a rotatably connected with a first hinge. This data display device has a main body that supports the display unit at a display angle. The main body is provided with a paper discharge unit for a built-in printer. The main body is rotatably connected to rear support cover via a second hinge. The data display device may be used in an operator mode, a first user mode in which the display unit is inclined in the direction opposite to the display angle for an operator by the second hinge, and a second user mode in which the display panel is rotated at an angle of inclination larger than the display angle for an operator by the first hinge.