Abstract : Enterprises are focusing more and more on knowledge issues for global product development. This paper describes knowledge evolution processes in product development activities and proposes a knowledge evaluation method in product lifecycle design. The paper also theoretically analyzes the evaluation model and illustrates how knowledge values can be assessed by case study. The case study shows how knowledge values calculated by the model can provide suggestions about which knowledge to choose and what to do next. The knowledge evaluation model serves as a useful tool for managing knowledge in product lifecycle design and support.