A study was conducted to obtain basic data on frontal crash deformation of compact cars (mini-sized motor vehicle). A compact car is lighter in weight than the other type of passenger cars due to the category size. In case of a ordinary passenger vehicle to compact car crash, it was assumed that the deformed value which leads to a higher speed as a barrier equivalent velocity becomes bigger than that of a ordinary passenger vehicles. For analyzing a frontal crash characteristics of compact cars, three experimental collisions which compact cars were crashed to a frontal full-lap barrier with velocities of 85 and 100 km/h and half-lap offset barrier with velocity of 85 km/h were performed. This study deals with the process of frontal deformation and the energy absorption diagram of the compact car body, and these are discussed to compare with the publicized data on small passenger vehicles. Further, the collision velocity of a compact car during an actual traffic accident is estimated from the energy absorption diagram which is obtained from this experiment, and the difference between the conventional calculation method and the newly introduced method is discussed in case of a frontal full lap collision.