This paper discusses how ontology helps case-based reasoning to provide better FAQ services. The proposed CBR technique works as a FAQ proxy service between the users and the backend process of a FAQ system. It can reason about adapted answers for given user queries, with the help of domain ontology, from past query cases stored in the case library, which is then fine-tuned according to the user feedback. The technique employs the semantics of PC ontology, in particular, the VRelationships semantic, to determine similar cases, perform case adaptation, and maintain cases. It also self-improves itself by tuning the survival value of each case in the case library in accord with user satisfaction and case similarity, which in turn are both user-oriented and ontology-supported. Our experiment shows the ontology-supported CBR takes up around 40% queries, leaving about 60% of the queries for the backend process to take care, which can effectively alleviate the overloading problem usually associated with a backend server.