Nowadays one of the most importance thing of developing a new car is lightening weight of vehicle. Therefore most of car makers make efforts to build up skills to lighten their vehicles. However, it is difficult thing to reduce weight of vehicle within maintaining their quality and cost of vehicle. Furthermore, it is not easy to apply a new technology because some parts on vehicle could affect safety of passengers. So before a new technology applies on vehicles, we must verify its feasibility and side effect of vehicle. As for this paper, we made lightened windshield glass that is more lighten 25% than windshield glass currently in use on vehicle. And we verify feasibility of lighetened windshield glass through various evaluation methods. In this paper we have attemped to define the possibility of applying lightened windshield glass on new vehicles.