As a preliminary work for the clothing conformity study, Its theoretical backgrounds were reviewed. In the view of convertibility into clothing conformity, two prevailing conformity types were studied. One is normative-social influence and informational-social influence classified by Deutsch and Gerard. And the other is Kelman`s classification which includes compliance, identification and internalization. Reference group, as an object of conformity, was studied. In addition to Engel and Blackwell` s and Assael`s classification, the reference groups which were revealed in the studies of consumer behavior and clothing behavior were reviewed. The factors were reviewed which influence conformity and clothing conformity. They were product factor, group factor, situational factor and individual factor.