Caring customer opinions and paying attention to its beliefs not only leads to organization attachment, but also causes the customer feels a component of the organization; therefore, such satisfaction may also be the key to bank achievement. Thus, the objective of the present research is to study the relationship between quality of service dimensions and customer satisfaction in different branches of Saderat Bank in Shiraz. This is an applied research in term of objective and is a survey in term of data collection. Data were collected through using questionnaire. Moreover, variables’ reliability was examined using Cronbach alpha coefficient. Data analysis and research hypothesis testing were conducted using SPSS software and t-student and binominal tests. Research findings indicate that all quality of service dimensions (quality of Service, customer accessibility, service characteristic/feature, and considering customer complaints) influence customer satisfaction in Saderat Bank branches.