This paper is on the Kasaya that reveals conspicuously the religious meaning among the Korean Buddhist costumes. The Kasaya has the most special meaning among Korean costume culture. It has the most important historical value, for Buddhism is the oldest religion that begins at 4th century A.D.. It has the most unordinary shape that we could not find any other costume culture. It has very important meaning to study on the Kasaya in the religious and cultural history of Korean costume. We have to study Korean Kasaya from surveying Indian Buddhist Kasaya diachronicaly. Buddha establishes himself the rules of weaving, coloring and wearing Kasaya. Bunso costume(분소의)is the first shape of Kasaya that he has worn during his ascetic practice. Bunso costume was a kind of shari. It is made with diapers those clean ordure of baby It symbolizes the life of ascetic practice. However Buddha could not stick to it as the only costume of monks. From his age Buddhist devotees have thought Buddha and monks as sacred beings. So they eagerly want to Provide the sacred beings with foods. clothes and other things that samgha(승가) need to live and accomplish their duties. At that time there are many kings, aristocracies and rich merchants among the devotees. They often offered them the luxurious silk Kasaya. that the ascetic monks could not wear. to express their deep faith. So the rules of the samgha has been distorted. The samgha has enlarged day by day as a great huge religious association. There are many different shapes of Kasaya. The Buddhist samgha need to establish a minute and rigid rules of Kasaya to order living of monks and to teach the moral and educational life to ordinary people. That book of rule is Vinaya pitaka(율장) . There are many kinds of Vinaya pitaka. This paper surveys the rules of Kasaya from Southern Vinaya pitaka(남전율장). This study will be the basic ground to research the Korean Buddhist Kasaya.