Companies are trying to decrease product expenses while customizing product according to customers requirements. So to satisfy the customers’ requirements, companies must adapt their business to mass customisation.  Mass customization final product goes through all flexible company production technology process, which can lead to being expensive and time-consuming and because of this, a product configuration system is developed to reduce product cost and reduce time. The primary focus of this thesis is to develop a KBE prototype using constraint-based techniques of product configurations. For developing KBE implementation of  UML/OCL, XML, Backtracking search is used. Then prototype expert configurator is developed using OCL constraints.