Abstract: In order to satisfy the user's retrieve need promptly and accurately, and retrieve the information which the user need from a lot of text files, firstly a concept semantic space based on concept space of documents is established, then based on it establish an index system with the association function; secondly a retrieve interface with intelligent function based on large semantic dictionary was made for the system. The retrieve interface can analysis the keyword that user input, and make sure user's really retrieve needing. According to the results of experimentation, it is clear that the retrieve efficiency and accuracy has been improved using this method.