Parameter and tolerance design are used to reduce the cost of production and improve the robustness of product. We consider the effects of model parameter uncertainty and quality loss function coefficient, and propose a parameter and tolerance economic design approach based on confidence level and entropy method. The proposed approach consists of parameter design stage and tolerance design stage. In parameter design stage, we obtain the best design variables through maximizing the confidence level of quality characteristics. In tolerance design stage, we get the quality loss function coefficient through entropy method, and then obtain the best tolerances through minimizing the total cost function which is composed of quality loss cost and tolerance cost. In this paper, we have analyzed the amine addition experiment of resin production process and studied the influence of temperature, agitation and rate of addition on the viscosity of resin systematically. Experimental results indicate that the optimal design variables and their tolerance values obtained by the proposed approach minimizes the effects of model parameter uncertainty while reducing the quality lost and tolerance cost.