HEAD-UP DISPLAY DEVICE

A head-up display device includes a casing provided inside an instrument panel. The casing includes an upper case constituting an upper part of the casing and provided with a fragile portion that is configured to be broken when an impact load is input to the casing from an upper side in a vehicle up-down direction, and a lower case constituting a lower part of the casing, provided with a light source unit configured to emit image information, and having a rigidity higher than that of the upper case.