To provide a clear and user-friendly liquid crystal display device to be used for mobile electronic equipment or the like.

A liquid crystal display device comprise: a liquid crystal display 5 for displaying normal-size characters as well as larger-size characters; an operation keys 2; font data of a plurality of display character size; a CPU 1 for selecting desired font size; and a liquid crystal control unit 4 for changing a display character to a selected font. The CPU 1 changes key assignment of the operation keys 2 in accordance with selected font size.