To provide a head-up display device which is rich in decorating property and can improve merchantability.

A head-up display (HUD) device 1 includes a display unit 20 that radiates display light representing a displayed image, and the device guides the display light to be incident to a combiner 50 and allows an observer to visually recognize the displayed image. The HUD device 1 includes a decorating part 131 disposed on an optical path of the display light from the display unit 20 to the combiner 50 in such a manner that an image of the decorating part is projected onto the combiner 50. The device includes an inner casing 13 storing the display unit 20 and has a radiation port 130 where the display light is radiated. The decorating part 131 is formed in a periphery of the radiation port 130 of the inner casing 13.