The main goal of every business is to create and retain customers. But many companies are more concerned with creating new customers than the retention of existing customers. Though, by the increase in customer retention can increase long-term profits. This research was aimed to analyze the effects of service marketing mix on customer retention of Islamic banking saving accounts in Pekanbaru. The research was conducted quantitatively with causal and descriptive research design. The amounts of sample are 154 customers of several Islamic banks by using a purposive sampling method. The data collection technique used in this research were surveys and observations. The data analysis technique used is Structural Equation Modeling (SEM). The results showed that all dimensions of service marketing mix affect significantly positive toward customer retention except for price, place and physical evidence variable