An approach of product configuration based on uncertain demand of customers is put forward to realize the mass customization(MC) . The demand of customers and product property values are converted to the triangular fuzzy numbers firstly in this approach, and the similarity is calculated after the normalization. And then the simple additive weighting ( SAW) method is taken as the utility function to derive the products which have the maximum similarity to the demand of customers. Finally, the digital camera is taken as an example to further verify the feasibility and the validity of this approach.