This study aims to measure customer satisfaction in Libyan banks which operate under the Islamic window system, by examining the dimensions of the perceived quality and their effects on customer satisfaction. Using the modified SERVQUAL model, the dimensions of the service quality to be examined are: Tangibility, Assurance, Reliability, Responsiveness and Empathy. This study also examines the awareness level of Libyan customers on various Islamic products such as the understanding of the key concepts of banking service, namely mudharabah, musharakah, murabahah, ijarah financing and a number of interest-free bank services. 366 samples were taken from three commercial banks in Libya which have been adopting the window Islamic system namely Gumhouria Bank, Wahda Bank and Sahara Bank. The researcher used Cronbach Alpha to measure the reliability questionnaire. Finally, the researcher performed the multiple regression analysis to determine the relationship between customers satisfaction and the five dimensions of service quality as indicated by the SERVQUAL model. The study finds that there is a positive and significant relationship between customer satisfaction and constructs of service quality like Tangibility, Responsiveness, Assurance and Empathy, with the exception that the Reliability dimension does not have any effect on customer satisfaction. The results of this study will be useful for policy-making by authorities in Libya that are responsible for the development of banking sector, especially the Islamic banking window system. Future research is needed to study further on the readiness of the customers for a full fledged Islamic banking operation. � IDOSI Publications, 2013.