The Artificial Intelligent and
Semantic Web have provided both new possibilities and challenges to automatic information processing in
search engine process. The major research tasks involved are to apply appropriate infrastructure for specific
digital library system construction, to enrich metadata records with ontologies and enable semantic
searching upon such intelligent system infrastructure. We study improving the efficiency of search methods
to search a distributed data space like a Digital Library. This paper outlines the development of a Case-
Based Reasoning prototype system based in an ontology for retrieval information of the Digital Library
University of Seville. The results demonstrate that the used of expert system and the ontology into the
retrieval process, the effectiveness of the information retrieval is enhanced.