D-S evidence synthesis formula has some insufficiencies,a new method based on information entropy theory was presented to focus on the conflict between original theory and peoplés normal judgment when the theory was used to solve problems with o-versized conflict. In the paper, a method of using the difference of evidence data to substitute conflict factor in evidence theory was proposed with information entropy theory to determine the proportion of focal elements. During the process of weighting the evidence, the concept of exponent entropy was used to solve the problem of convergence. The method proposed in this article emphasized its superiority compared with other algorithms on matters of processing evidence conflict and one vote veto system.