The traditional IPA model has been considered to be a decision-making tool for service quality management.However, the IPA model does not meet the assumptions of the service quality gap, and alsocannot explore the connection between service quality attributes, which can easily lead to decisionmakingerrors of service quality management. The purpose of this study is to apply the IPGA model andDEMATEL to explore the service quality improvement priority of fine-dining restaurants and the causalrelationship between service quality attributes, and use it as the decision-making reference of servicequality strategy planning and resource reorganizing for the restaurant industry with limited resources.The study applied the customers of 8 fine-dining restaurants in Taipei City as the study object, and thereare 502 effective samples. The study result shows that the dimensions of reliability, responsiveness, andassurance are concentrated here, and are the restaurant service quality dimensions that most need to be improved from the customer perceptive. In addition, the total effect of reliability is the highest among all the service quality dimensions. Reliability and responsiveness, in addition to impacting each other, will impact assurance and empathy. According to the study result, through IPGA and DEMATEL, the service quality performance of fine-dining restaurants and the resource input priority can be grasped more objectively and accurately, which can be used as a reference for manager to plan the service quality improvement strategy