The primary aim of this study was to analyze the fashion trend of wearing T-shirts with slogans at home and abroad and to consider the social influence of these shirts on fashion. The research method was based on the documentary method and the existing literature, and the study range was limited to the period from the middle of the 20th century to the present. Slogan T-shirts played important roles because they make the wearers highly visible wherever they go. T-shirts with slogans not only intentionally expressed the wearers’ views on multiple social issues but they also made those issues more visible, thereby encouraging society to deal with them. The T-shirts also helped to form a social consensus regarding the issues. For this reason we referred to slogan T-shirts as ‘the social fashion’ in this research. Regarding the results, the research found that T-shirts with slogans were a social fashion that conveyed real political slogans and thus influenced people’s political beliefs. Second, they politicized the issues in public interests with the public perspective. Third, the purpose of slogan T-shirts was to help people express their personality publicly and thereby bond with other people who held similar sympathies. Furthermore, the T-shirts conveyed multiple meanings in each message.