Abstract: Considering the theories of matter-element and vague set, a model of matter-element decision making under vague environment was proposed. The definition of vague sets was introduced and the compound vague matter-element was defined. The positive-ideal solution and negative-ideal solution of scheme matter-element were established by an improved order function of vague values. According to the similarity measure of vague values, the distances between scheme matter-element and ideal matter-element were calculated, and the best scheme could be selected by the rule of closeness degree. A numerical example is given to apply the proposed method, and the result shows that the proposed method is available for vague and uncertain decision making problems.