Recent advances in Web and information technologies have resulted in many e-learning resources. There is an emerging requirement to manage and reuse relevant resources together to achieve on-demand e-learning in the Web. Ontologies have become a key technology for enabling semantic-driven resource management. We argue that to meet the requirements of semantic-based resource management for Web-based e-learning, one should go beyond using domain ontologies statically. In this paper, we provide a semantic mapping mechanism to integrate e-learning databases by using ontology semantics. Heterogeneous e-learning databases can be integrated under a mediated ontology. Taking into account the locality of resource reuse, we propose to represent contextspecific portions from the whole ontology as subontologies. We present a subontology-based approach for resource reuse by using an evolutionary algorithm. We also conduct simulation experiments to evaluate the approach with a traditional Chinese medicine e-learning scenario and obtain promising results.Index Terms-Semantic Web, collaborative learning, information resource management, knowledge reuse.