Today’s competitive business environment imposes new challenges to manufacturing com-panies. For these companies to survive in this environment, implementing product life-cycle management (PLM) technologies with an emphasis on cost control is one validapproach. PLM is a strategic business approach that applies a consistent set of businesssolutions to help manufacturing companies manage all the activities related to a productin an integrated way across the lifecycle from customer need to product recycling anddisposal. Product lifecycle cost is an important measure for PLM implementation. It canhelp track and analyze the financial information of activities associated with each phaseof a product’s lifecycle. The paper presents a framework of the product lifecycle costingsystem for supporting decision making, especially the decision making at very earlystages of a product lifecycle. It can be used as a design support tool to help new productdevelopment. A number of methodologies and tools are developed in the system. The casebased reasoning method is used to quickly build a new product model. The costs ofproduct development processes related to the new product are calculated using activitybased costing methods. Dynamic programming is then used to obtain an optimal set ofproduct development processes with the objective of optimizing the overall product de-velopment cost. This system is built using object oriented modeling methods.