A customer satisfaction model is proposed for optimal product design , combining design budget , some technical requirement and imprecision. New concepts of actual achieved degree of attainment and planned degree of attainment of DAs are introduced in this paper. A parametric programming technique is developed to solve this mod2 el . With this model , more than one solution can be obtained for design engineer under different possibility levels for satisfying the design budget . An illustrated example is also presented in this paper.