Boston Consulting Group Matrix (BCG) is an analysis tool for formulating the company's strategy. The purpose of this study was to determine the market growth and relative market share of PT Bank Muamalat Tbk.. This research uses descriptive qualitative method. Research was conducted at PT Bank Muamalat Indonesia Branch Office Singosari. The data used are primary and secondary data. Research focused on market growth rate and relative market share of PT Bank Muamalat Indonesia. The main competitor is PT Bank Syariah Mandiri. The results from the study showed a growth rate of PT Bank Muamalat Tbk . in 2014 amounted to 20.32% and have a relative market share of 0.94x (star). In 2015, company included in the cash cow because the company has market growth rate of -5.09% and the relative market share of 0.83x. Companies that included in cash cow quadrant has to be more careful in making investments and keep the cash inflows under control so the cash does not drop significantly. Investment should be made to improve facilities and customer service. The company is expected to be able to maintain its position and market dominance in order to not displaced by the competitors.