A head-up display device includes a housing, a reflecting member, a projection light emitting unit, and a vibration transmitting member. The housing is fixed to a vehicle. The reflecting member is rotatably supported by the housing and is held at a rotation position. The projection light emitting unit projects projection light corresponding to information onto a window of the vehicle through the reflecting member. The vibration transmitting member is provided between the housing and the reflecting member and has elasticity. The vibration transmitting member is fixed to the housing and makes contact with the reflecting member in an elastically compressed state in an entire rotatable range of the reflecting member.