This paper is appraised on theory foundation of law at the multi - level grey , to bring full play of all evaluation information in different grey degrees , and discusses the procedure of model creation . then it induces all evaluators " distributive information into one priority - vector of different grey degree and allocates it with single value so a comprehensive value is obtained for the project under evaluation . the decision of sorting project to be evaluated then can be carried out 在多層次灰色評價法的理論基礎上,為了使描述各灰色類的評價信息都發揮作用,將被評者的分散信息處理成一個描述不同灰色類的權向量,對其進行單值化處理,可得到被評者的綜合值,從而對被評者排序選優。