This study aims to: 1) know peer relationships; 2) know the use of Muslim clothing; and 3) know how peer relationships influence the use of Muslim clothing. This research is an ex post facto research with quantitative approach. The populations in this study were female students of Universitas Muhammadiyah Yogyakarta. Samples taken were 55 respondents with random sampling. Data collection was done by questionnaires and interviews. Data were analyzed descriptively. The hypothesis was tested using simple regression analysis. The results of the study show that the most influential indicator from peer relationship is closeness. For the use of Muslim clothing, the most influential indicator is the clothing that does not resemble disbeliever women’s clothing. There is a significant influence of peer relationships on the use of Muslim clothing. Influencing variable on the use of Muslim clothing effectively contributed 7.7%.