To prevent distortion in a light reflection direction and enable a specific light distribution characteristics to be ensured by partitioning an inner face of a headlight body into a bottom side inner face and an opening side inner face and forming a reflector face on the bottom side inner face only due to metal evaporation.

A headlight body 8 inner face of a head light device is partitioned into an bottom side inner face 10a and an opening side inner face 10b on an opening 8a securing a crystal lens 9, and a step 15 is formed therebetween. A reflector face 16 is covered and formed for the bottom side inner face 10a only by means of aluminum evaporation. Thus, since the reflector face 16 is formed for a necessary part for light emitting a parallel light rays from a lamp 14, a distortion in the reflection direction when the reflector face is formed on the entire inner face of the head light body can be prevented, and a desired light distribution characteristics can be ensured.