Hydro-forming technology is a technology that will replace the existing press-forming technology and is used in various industry range from automotive parts to electronic products. The advantage of this technology is that it has dramatically changed the existing processing method, and it can be said that the process reduction due to the reduction of parts, cost reduction, and high precision are mentioned. In this study, it is intended to present a design process using computer simulation by changing the sub-frame for automotive parts produced with the existing press forming technology to the hide-forming method. To this end, it is intended to use it as part design data by comparatively analyzing the cross-sectional shape and thickness reduction, which are the major factors necessary to determine the successful development of the developed parts.