Abstract: IHSMTS is an interactive hybrid strategy machine translation system proposed by the authors. In this paper, the case model acquisition mechanism of this system is described, in which multiple knowledge acquisition approaches are combined, including: interactive approach, extracting from the bilingual information generated by RBMT, case model refinement and extracting from parallel bilingual aligned text, and so on. In addition, it is possible to guarantee the suitable abstract level of the acquired model and the monotonic increment of case model by using the case model checker, which is designed to check the consistency and redundancy among the new acquired model and the existing models in the case model base. By using this kind of case model acquisition mechanism, it is possible to acquire a case model in various ways, and, as a result, enable the IHSMT system to amend its case model base dynamically, thereby improving its translation quality.