In this thesis, we proposed an automated ontological creation process, and focus on domain terminology’s relationship. By analyzing web pages on Wikipedia, an online encyclopedia, we constructed not only a dictionary but a semantically related words’ network. In order to fulfill the semantics’ need, we also proposed an algorithm to calculate the semantic distance between terms. The entire process can greatly reduce the human resource requirement in building a traditional domain Ontology. This system also provides a better support for domain-specific QA systems than a general purpose lexical dictionary in its flexibility and further offloads the semantic process burdened on QA systems.