The goal of smart tourism construction is to improve tourism service and tourist experience by using new general information technologies. In order to let tourist dialog with the electronic explanation system of scenic spots?by natural voice, an intelligent tourism explanation system based on natural language processing and ontology knowledge retrieval was put forward. Firstly, the physical view and logical view of system architecture was designed in this article. Secondly, this article analyzed the key technologies of text vector, named entity recognition, dialogue policy?management and tourism knowledge retrieval. Finally, a prototype was developed. It proves the system is feasible.