This study aims to develop a coat design for the new hanbok by applying the toile de Jouy textile design set in the background of Koh Un's excavated costumes and the Joseon Dynasty. As for the research methods, a literature review on excavated costumes of Koh Un and toile de Jouy, a field study on excavated costumes, and the development of a new hanbok coat design were conducted. The new hanbok coat design was developed and applied to the Korean toile de Jouy design and was simulated and presented through the CLO 3D virtual costume program. The new hanbok coat design consists of a total of four designs. Design 1 is a Jikryung which is a men’s coat. It is made of polyester and padding with the motif of a double knife-shaped collar, outer collar, triangular gusset, and goreum that connects by attaching a loop of Koh Un's excavated costumes. Design 2 is a Dallyeong coat for men with motifs such as the round collar, outer collar, triangular gusset, and large belt of Koh Un's Danryeong costume excavated. Design 3 is a Dapho coat for women. It is based on the double knife-shaped collar, outer collar, short sleeves, and goreum that connects by attaching a loop form from Koh Un's excavated costumes. The short Dapho sleeves were changed into puff short sleeves, and the goreum connects by attaching a loop with multicolored stripes. Design 4 is a women's Cheollik coat. It is based on the motifs of a double knife-shaped collar, longer top and shorter skirt, pleats, and the goreum that connects by attaching a loop of Koh Un's excavated costume. The lowered waistline of Cheollik in the early Joseon Dynasty was pleated in a flared skirt style with a drape and soft feel. All four designs were printed with a toile de Jouy pattern developed under the theme of Joseon classical scholars.