Abstract: Dezert-Smaradache thoery (DSmT) can well deal with the fusion of conflicting information, but the number of focal elements will greatly increase with the increment of the number of elements in frame of discernment, which causes the big computation burden. An improved method based on DSmT is proposed in this paper. In engineering applications, the conflicting focal elements are not very useful in the decision-making. Thus, we just calculate the basic belief assignment (bba) of the focal elements included in the frame of discernment, and the bba of conflicting focal elements is ignored. This is able to efficiently reduce the computation complexity, and improve the speed of convergence of mass function. The new proposed method is applied in the C4ISR system for identifying the radar radiation source. The simulation results show that new method can more accurately and quickly recognize the radar target with conflicting information than classical method.