A head light system for a vehicle using a discharge lamp together with glare stop structure provides a low beam mode and a high beam mode. The head light system includes a discharge lamp (4) mounted on a base plate (1), a shade (7) for selectively and partially shading light source (5) of the discharge lamp (4), and a moving means (K) for sliding said shade (7) relative to the discharge lamp (4) along an arrow (X) in a longitudinal direction of the discharge lamp (4). The shade (7) has a leg (7b) which penetrates the base plate (1), and the leg (7b) is coupled with an iron piece (9) in a solenoid (8) which is fixed to a rod (6) fixed under the base plate (1). The iron piece (9) is urged by a spring (10) so that shade plane (7a) of the shade (7) partially covers the light source (5) of the discharge lamp (4) when the solenoid is not energized so that low beam mode is provided. When the solenoid (8) is energized and pulls the iron piece (9) against the spring (10), the shade (7) slides so that said light source (5) is free from the shade plane (7a) to provide high beam mode.