To address the shortcomings of existing methods of pairwise comparison of alternatives generally constructing comparison relation on one grade rather than expressing a variety of different preference relations simultaneously, a new decision method based on pairwise comparison of alternatives on multiple grades is proposed. In the method, a symmetrical framework based distributed preference relation(DPR) on multiple grades is constructed on a set of alternatives. Through giving scores of grades in the framework, the score matrix of the DPR is calculated and used to construct a pair of optimization models to obtain the priority interval of any alternative, which is further applied to generate decision results. A selection problem of cloud service providers in a manufacturing enterprise is solved by using the proposed method, which verifies its applicability and effectiveness.