To secure vehicle safety performance in frontal crash is one of the most important factors in vehicle design. In late years occupant safety in frontal crash is getting better as vehicle crash characteristics such as cabin deformation and vehicle deceleration are improved. However, body mass is increasing at the same time due to necessary body reinforcement in order to improve the vehicle crash characteristics. This paper describes the practical multipurpose design optimization method using a simplified spring-mass frontal crash model to achieve the better vehicle crash characteristics with smaller body mass. The result of this study may be useful to establish the more rational decision-making process in vehicle design.