Abstract: Based on multi-grade dominance relations, this study develops a new multi-criterion decision model, which can avoid losing information when decision table is changed into PCT and obtain complete ranking of alternatives. The model introduces PROMETHEE II into dominance-based rough set theory and with different preference grades for different criterions, describes binary preference relations of two objects. Meanwhile, the model resolves the problem of some alternatives having the same net flow value, which is a common problem when rough set method is applied to MCDA. Finally, an example illustrates the model is scientific and validity.