In this research, questionnaire survey had been conducted on the customers of the commercial banks in financial holding company. Responses of customers in Taipei Metropolitan area are first analyzed by analytical hierarchy process (AHP) to evaluate the relative importance of the service quality determinants, then Ridit analysis are applied to explore the service quality perceived. Our major results are briefing as below:1. Among the 4 service quality determinants, service content and attitude is most important, followed by operating efficiency and Complaint handling. External influence is less important.2. Customers satisfied more about the attitude of bank employees and Internet related services, but less satisfied with how banks deal with their complains.3. Customers are not able to assort the quality of different service items.