The purpose of this research is to find and explain the effect of service quality, customer satisfaction, and relationship marketing to customer loyalty. Dependent variables on this research are service quality, customer satisfaction, and relationship marketing. The independent variable is customer loyalty. The method of this research is quantitative research. The population of this research is student management class of 2014 Faculty of Economics and Business University Muhammadiyah Purwokerto who have already used Simpati Telkomsel for at least three months. The sample for this research is 75 respondents with purposive sampling method. Data were analyzed with multiple linear regression. The results of this research show that service quality has a positive and significant effect to customer loyalty, customer satisfaction has a negative and insignificant effecf on customer loyalty, relationship marketing has a positive and significant effect to customer loyalty.