The industries are facing with the pressure to design products that could meet various customers requirements in short term. At the main time, there are a lot of existing 3D models are available from accumulation of years of design practice. It is therefore critical to extract similar models from existing ones for reuse. This paper proposes a feature based similarity access tools which describe the 3D using global features. It describes the similarity measure principle, the feature extraction process, histogram generation and comparison method. The method has been verified of its effectiveness with plenty of examples. It could discriminate target model among complex product model database.