The thought of three religious, Confucianism, Buddhism, and Taoism, had been the mainaxis of Korean spirit of the past. This study is centered on Buddhist and Taoist costume. There have been a lot of studies on Korean costume from many viewpoints. However, there have been few approaches to the inner !"ide of it. That is to say, the research on spiritual back-ground or religious correlation has not done yet. And especially, we are wholly lacking the studies on Taoist costume. In this dissertation, I investigate how they had come to wear Buddhist costume and how it trans, on the basis of related documentary records and existing remains. I also inquiry Taoist costume which was worn at Taoist ceremony in our country, with the help of Korean books and documents and of the sources of Packwoonkwan in China. In the case of Topobyunjeung in Korean costume, in particular, we can catch the source of it only after studying the religious side of Taoist costume and Buddhist costume. As revealed in the theory of Topobyunjeung in Ojuyunmoonja-ngsango by Lee, Kyu Kyung, even old masters and great Confucianists could not know whether Topo, the ordinary clothes of the Sadaeboo, originated from Taoist costume or Buddhist costume. There have been many opinions about the origin, but even now it is true that no one has made it clear. Therefore in this dissertatio I demonstrate mainly how Topo and Hakchangeui appeared in Korean costume through Taoist costume. It is said that Taoists, Buddhists, and literary men wore Topo, Chickchul, and Chickshin in Song dynasty of China. Topo was a clerical robe of Taoists and was also an ordinary clothes. Chick-chul was a clerical robe of Buddhists, and Chick-shin was worn by Zen priests in Won dynaty. Over the Po, Buddhist wore a large robe, namely Kasa, and Taoist wore Packhakchang like Wooeui, when they attended at the religious ceremony. And they regarded such manner of dressing as ceremonial full-dress attire. The style of Topo in China was Saryunggyogeo. The is th say that they put the black Yeon along Sajoo, which are Young, Soogoo, Keum, and Keo, and that they wore Sajodae around their waists so as to let the band down in front of them. Our existing type of Topo is that of Chickryung-gyoin. The characteristics of the type are its Koreum hung on the dress, no Yeon along Sajoo, and Soopok at the back of the dress. And when they put on the dress, they wear Saejodae around their waists. These characteristics considered, we can find the source of Topo from the Po of Chickshin among Buddhist costume. Other types of Topo are those that were transformed elegantly according to our national manners and customs in our country. So-called Wooeui in Chiness Taoism is Hakchang. Originally it was made by weaving for of cranes or other feathered birds. Its remarkable feature is the wide sleeves. Later they called such a robe with wide sleeves Hakchang. Our hakchangeui has Yeon along Sajoo and a belt around waist. We can guess that the features of Topo and wide-sleeved Hakchang mingled and turned into Hakchangeui. Or it might also be that Topa worn by Taoist was regarded as Hakchang and Topa which has Yeon along Sajoo was regarded as Hakchangeui in our country. Such type of Hakchang worn by Taoists was well shown in the Buddhist and Taoist paintings among "The Pictures of Hills, Waters, and Folks" in the latter half of the 16th century. In China Hakchang with a belt around waist could not be seen. Comparing our style of Hakchangeui with the Chinese style, we can recognize the former was similar to that of Chinese Topa. From this, we gather that Topa was regarded as Hakchang, Wooeui worn by Taoists, Ascetics and True Men in Korea. Furthermore I also gather that our Hakchangeui, which has Tongjeong, Koreurn and a belt around waist, was a transformed style in our own country. From the above, we can realize that in costume the three religions, Confucianism, Buddhism, and Taoism, cannot be treated separately although they are different each other in the essential thought. We have to recognize that Korean Costume was established under the closely connected correlation among the religions and that it was transfigured and accepted according to the cultural characteristics. This study is significant in that it is the first attempt to understand Korean costume through the religous approach, which has never been made in our Korean costume studies. We are demanded even more wide and profound investigation on the religious side of costume throughout the general field of costume studies.