Semantic　retrieval　method　stands　at　the　crossroads　between　Natural　Language　Processing　and　Machine　Intelligent.　This　paper　makes　analysis　on　the　semantic　search　method　and　research　on　concept　similarity　algorithm,　and　discusses　the　factor　of　weight＇s　influence　on　concept　similarity　as　well.　On　this　basis,　this　paper　proposed　a　new　semantic　search　method　based　on　ontology,　and　apply　it　to　the　tourism　information　retrieval,　which　intellectualized　tourism　information　retrieval　service.　©　(2014)　Trans　Tech　Publications,　Switzerland.