The purpose of this study was to identify the determinants of decision-making confidence of clothing. As determinants, this study examined consumer susceptibility to interpersonal influence, vanity, and clothing knowledge. Data were collected through surveying university students in Seoul metropolitan area using convenience sampling method. Out of 324 distributed, 300 useful questionnaires were returned. The results showed that identical conformity among consumer susceptibility to interpersonal influence factors significantly influences, both directly and indirectly, decision making confidence through vanity. Although normative conformity does not influence decision-making confidence directly, it does significantly influence decision-making confidence indirectly through influencing vanity and clothing knowledge. The results suggest clothing is a manifestation tool for managing public self, which finally leads to increased clothing knowledge and decision-making confidence of clothing. These findings may be used by marketers in developing strategies for product development and promotion.