通过对现有参数化求解方法的分析,提出了一种基于图论的参数化求解方法,该方法能方便地确定几何元素的求解次序,然后采用几何推理与数值计算相结合的方法生成满足要求的设计图纸,并对如何处理局部修改产品外形时约束集的维护进行了讨论“,”Through analyzing the available parametric solving methods ,a graph theory based parametric solving method is presented in this paper. With the method ,the relationship between the constraints and the geometric elements can be easily established, and the desurable design drawing can be generated through geometric reasoning and numeric iteration. The maintenance of geometric constraints when the product shape is changed is also discussed.