Abstract: Dempster combination rule,which is a classical combination rule of D-S theory,involves counter-intuitive behaviors when the evidences highly conflict with each other.A modified combination rule is proposed to solve this problem.An easily ignored problem is discussed first—how to define the degree of conflict between two evidences more reasonably,then a reasonable definition of the degree of conflict between two evidences is given.Based on it,a modified Dempster combination rule is proposed,which has the superiority of information focusing like a classical Dempster rule and avoids the unreasonable combination results when evidences conflict with each other.The advantage of the proposed rule is tested through simulation.