The purpose of this study is to investigate the origin of ku and changes of styles from ancient times to recent times. It will contribute to recent times . It will contribute the correct understanding of the historical change of clothing materials. For this study historical comparative method were utilized using documentary records and relic of ku. The results of this study can be summarized as follows. 1. The fur clothes were the first clothes that human beings put on in order to protect human body against the cold. Ku was widely worn by many people in Asia dynasty. ku was an out fit for protection against the cold and it was made of animal fur. 2. The ancient times, the northern part of korean peninsular and Manchus were the mainfield of action of korean people. At this time, koreans preferred the ho-bok that the nomadic tribe used put on. But the territiory of unified Silla was limited to the southern part of korean peninsular, and it be supposed that ku was preferred only in a certain local community and social class. In Chosun dynasty , ku was also adopted as garment for protection against cold. During Sung-Zong and Chung -Zong era it was so popularized that both men and women in noble class preferred it. But in latter part of Chosun dynasty government worned the nation against extravagance in living, ku lots its popurality and it was modified into another garments such as gotzaugori, baeza and magoza.