The armored structure is exposed to the outside of the target in the combat environment and becomes the primary target of fragmentation. In order to study the multi-mode damage caused by fragmentation, a set of multi-mode damage probability calculation and analysis method was established based on the armored structure penetrated by fragmentation. Based on LS-DYNA simulation calculation, each damage mode was analyzed and the threshold point was determined, and the armor structure damage simulation phase diagram with speed and angle as two-dimensional input variables was drawn. The intersection problem of fragments and armor structure was solved based on the calculation of the intersection point of ray and plane. The solution result was input into the damage simulation phase diagram as input variable, and the output result of the damage simulation phase diagram was used as the criterion of each damage mode. The damage probability of each damage mode under fragment penetration of armor structure was calculated by Monte Carlo method, and the damage probability curve was established. The visual output platform was built and the multi-mode damage cloud image was obtained according to the experimental matrix calculation. The results show that three damage modes, ricochet, penetration and penetration, can be formed when the fragments hit the armor structure at different speeds and angles. The program can calculate the damage probability of each damage mode and output the damage cloud map.