This study is to help maintain the identity of traditional Korean culture and develop fashion culture products by applying images and composition forms of traditional lattice patterns for vest designs. Lattice can be distinguished as a shape created through intersecting vertical and horizontal lines, in the form of oblique lines in vertical and horizontal structures, and in the form of an oblique line. Lattice patterns represent the overall unity and order as well as the beauty of small spaces created by simple lines. Traditional lattice patterns of the Joseon Dynasty were examined theoretically through the literature. Based on theoretical grounds, there is study illustrates vest designs using Adobe Illustrator CS6 as well as works on a 3D virtual costume using CLO Trial 4.2, a 3D virtual dressing system of CLO Virtual Fashion. This study developed an easy to wear vest design categorized as clothes for both men and women. The geometric formality of the lattice pattern has been applied to fashion culture products. In this study, the design was developed focusing on lattice, kotsal (flower pattern), sosulbitsal (diagonal), sotdaesal, tisal (horizontal & vertical). This study can be used as basic data in the domestic fashion cultural product market that can help maintain the originality of Korean culture in the global era that also assists in the successful promotion of Korean culture and traditions.