This study is on the classification of Chchori forms in Korea in the 16 th and 17 th Centuries by investigating the patterns an construction of excavated clothong. The characteristic features of the Korean Chchori in the period are as follow. 1. The Chchori shows forms. The diversity is accomplished by varing the components pattern is Chchori, such as collar, sleeve, and bodice. The divertification in Chchori pattern represents an attempt to advance the simple Chchori pattern in the 4 th and 5 th Centuries to the mordern one. 2. Mokpankit (목판깃) has a straight construction line but Kalkit (칼깃), Dangkogit(당코깃) have curved one. This suggests a transformation in the construction line of Chchori. 3. Among Chchori pattern, some Mokpankit and Kalkit Chchori show two kinds in size ; 40-50 cm and 60-70 . However, Dangkokit Chchori has only one size of 40-50cm. Considering the difference in body size between man and woman , Mokpankit Chchori and Kalkit Chchori are jueged to be for man and woman commonly, and Dangkokit Chchori is for woman only. After the period , woman wears only Dangkokit Chchori, whichis thought to come from the sex discrimination. Consequently on the viewpoint of rinsiple of Adaptation to Environments, forementioned facts prove the changes in Korean society in the 16 th and 17 th centuries on the historical basis of costume.