The development of Sharia Banks in Indonesia was exceedingly rejoicing in the early years of the establishment of the first Sharia bank, Bank Mumalat Indonesia, in 1992. This development was followed by many conventional banks spinning off into Sharia Banks. However, lately, the development of Islamic Banks in Indonesia has been discouragement. This can be seen from the market share of Islamic banks that have relatively no increase from year to year. Seeing this condition, researchers are interested in conducting research on the loyalty and switching intention of Bank Muamalat Indonesia customers, who are the first and pioneer of Sharia Banks in Indonesia. The purpose of this study is to look at the effect of Bank Muamalat Indonesia's service quality and switching cost on customer intention switching with loyalty as a mediating variable that can explain this effect. This research was conducted on Bank Muamalat Indonesia customers with a total sample of 168 respondents taken through convenience sampling and using SEM AMOS as a data analysis tool. The results of this study indicate that service quality and switching costs have a positive effect on loyalty, and loyalty has a negative effect on switching intention. In addition, loyalty can also fully mediate the influence of service quality and switching costs on switching intentions