There are some important that development of tools to retrieve information by simple operation in large of nave users in the world wide web. In general, query formulation method and operators are variety, not easy to formulate query in information retrieval system or web based retrieval engine. In this paper, we propose "Concept Wizard" to support query formulation with concept term expansion in natural language query information retrieval system. The Concept Wizard are interactively supporting query formulation using thesaurus and Providing plug-in on the web.