Abstract In order to solve the problem of design evaluation in the stage of plan selection in industrial design, a new angle and method for design evaluation research by using Priority-degree Evaluating Method is proposed. In this paper, by determining the measure index, setting weight coefficient, calculating association degree and priority-degree, the design plans of three Air-Water Making Machines (Air-WMM) were evaluated comprehensively and quantitatively. By comparing the priority-degree of the three design plans, it provides quantitative suggestions for client companies to select design plan effectively. The Priority-degree Evaluating Method can effectively reduce the adverse effects caused by many factors to be evaluated in design evaluation, large dependence on the experience and knowledge of the evaluator, and difficult to judge the relationship between each factor and the final plan. Our evaluation method has got good feedback and effect in the process of negotiating with Client Company.