Considering the complexity of airport industry service offerings, it is important to identify which airport service attributes detract from passenger satisfaction and which attributes enhance it. Therefore, this study presents an IPA-Kano model to classify and diagnose the service attributes of an airport and suggests opportunities for service improvement. The model is validated through a case study of Taoyuan International Airport (TPE). The model combines the Kano model quality categories with the importance and performance of each service attribute and is developed for classifying and diagnosing service attributes at the TPE airport. As shown in this study, the proposed approach could help managers determine a correct and effective service improvement strategy for their airport. Another characteristic of the approach is its simplicity—advanced statistical knowledge is not required.