This study, focusing on the costumes of Kouge in the era of Kamakura and the end of Heian in Japan, aims to explore the aspects and characteristics of the costumes that were developed under political, economical, and social circumstances. The findings are the following. Male costumes include Sokdae, Pogo, Euigwan, Jikeui, Sueui, and Sugan, while female costumes include Shipidan, Sogyu, Sejang, and Hansam. Different clothes of Kuge were chosen depending on the types and purposes of the occasions: full dress and Yahkjang, a semi-dress, for a ceremonial purpose, street costume for a personal visit purpose, outdoor clothing for hunting and outdoor activities, Cheongjangsok, and Sukjikjangsok. In these various types of clothes we can assume the elegant life of aristocratic class of Kouge. In addition, different fabrics, patterns, and dresses were chosen depending on the grade of ranks of Kouge, so that Kouge can differentiate their ranks, keep the order of the ranks, and enhance their authority by themselves. With the advent in the era of Kamakura, the power of Kouge was weakened and their clothes underwent changes, some types of clothes were omitted or simplified or the clothes of subordinates were worn. In addition, when new forces appeared and new clothes came about, there were changes in the purpose and the wearer of the clothes: from ordinary clothes to official clothes, from the clothes of lower class to the clothes of higher class, and from Sukjikjangsok to Cheongjangsok.