The product configuration modeling is a key technology to realize configuration design.Most of the researches were mainly conducted focusing on how to establish a product configuration model,but were short of the consideration about the application scope and dynamic change features.In this paper,the reconfigurable modeling technology of similar-structure products configuration design is studied to enhance the generality and diversity of product configuration models,and to facilitate the dynamic upgrade of configuration models.The configuration components of products with similar structures are divided into sharable configuration components,essential configuration components and optional configuration components,so the construction of reconfigurable model of configuration design can be converted into the set operation of configuration components.The horizontal adjusting reconstruction of configuration model is carried out through the adding,replacing and deleting of configuration components,the vertical adjusting reconstruction of configuration model is carried out through the parametric deformation of configuration components,and the variable topological configuration model reconstruction can be realized through the transformation of partial structure of configuration components.Finally,NC machine products are used as an example to analyze and verify the reconfigurable modeling technology of products with similar structures.The speed of NC machine configuration design is found to be improved,and the number of NC machine configuration design models is decreased.And the reconfigurable design system of NC machine products is developed.The proposed modeling technology provides references for the processes,methods and steps of model reconstruction. The product configuration modeling is a key technology to realize configuration design. Most of the researches were mainly conducted focusing on how to establish a product configuration model, but were short of the consideration about the application scope and dynamic change features.In this paper, the reconfigurable modeling technology of similar-structure products configuration design is studied to enhance the generality and diversity of product configuration models, and to facilitate the dynamic upgrade of configuration models. The configuration components of products with similar structures are divided into sharable configuration components, essential configuration components and optional configuration components, so the construction of reconfigurable model of configuration design can be converted into set operation of configuration components.The horizontal adjustment reconstruction of configuration model is carried out through the adding, replacing and deleting of configuration compon ents, the vertical adjustment reconstruction of configuration model is carried out through the parametric deformation of configuration components, and the variable topological configuration model reconstruction can be realized through the transformation of partial structure of configuration components .Finally, NC machine products are used as an example to analyze and verify the reconfigurable modeling technology of products with similar structures. The speed of NC machine configuration design is found to be improved, and the number of NC machine configuration design models is decreased. And the reconfigurable design system of NC machine products is developed The proposed modeling technologies provides references for the processes, methods and steps of model reconstruction.