Abstract: Based on database technology and designing method of modularization,adopting production rules to express knowledge,database knowledge with a large amount of data of wear resistant materials,experience knowledge of expert and principle of materials selection had been established,the whole frame of the materials selection expert system of wear resistant materials had been designed.The system realized store and inquiring of wear resistant materials quickly.By simple judgment,materials selection of typical part machining models,using modern method of generalization,and goal,materials selection,the system provides scientific evidence and technological guidance for wear resistant material using,production and development of new material.