This paper studies the effect of the slenderness ratio on the dispersion characteristics of the aimed KE-rod warhead, with the nonlinear dynamic analysis software LS-DYNA, 11 different slenderness ratios of the KE-rod are considered, and the relationship among the KE-rod speed, the spatial distribution and the slenderness ratio is obtained When the slenderness ratio is greater than 5 and less than 11, the speed of the KE-rod increases with the slenderness, and when the slenderness ratio is greater than 11, the speed decrease slowly; for the spatial distribution, when the slenderness ratio greater than 5 and less than 8, the spatial distribution of the KE-rod is more intensive, when the slenderness ratio is greater than 8, the distribution is relatively dispersed and uniform, when the slenderness ratio is 11, the velocity and spatial distribution of the KE-rod is optimal. The simulation results are basically consistent with those in the literature, and differ slightly with those obtained by experiments. The simulation results can provide a reference for the design of this type of warhead.