The importance of design change management in engineering product development has been widely reported. However, most research focuses on the engineering change in the manufacturing phase, the later phase of product development. In this paper, a reference model for design change management has been proposed. A modelling method is employed to enhance the traceability of changes occurring between the functional model and the structural model. A matrix based method has been developed to capture change propagations at the structural level and the parametric level of product design. A structural method of change propagation analysis and change impact evaluation has been developed. Finally, conclusions are drawn and scope for further work of this research is indicated.