Abstract: Create a new competitive environment in the banking industry, makes the need for more attention to the demands, needs and expectations of our customers and offer consistent service and beyond their expectations, inevitable. Banks should be able to changes in procedures and policies of their marketing, they meet the expectations and needs of customers, otherwise, they have no place in the financial market in the future in contrast, their age and experience. This study has been done as the effect elements of the marketing mix of services to customer preferences in selecting a bank in Khorramabad City in 2011 in the branches of Saderat bank which this study has been investigated with the 8 hypothesis in relation to each of the marketing mix and relevant indicators and to identify and assess their importance. This research is part of applied research in terms of purpose and this research is a descriptive research, in terms of the nature and procedures. The populations of this study are all normal customers of Saderat bank branches in Khorramabad. That we used a sample of 150 customers from different branches of Saderat bank in the city of Khorramabad to test the hypothesis, they were selected randomly. We used the method library and a questionnaire to collect data.