In order to study the damage efficiency of the fragment for the target, puts forward to adopt Poisson probability distribution function analysis fragment group distribution rule; According to the target features and Poisson probability, using the target center to establish damage vulnerable area of the mathematical model; Through the flinders damage each tank section full probability and mutual independence hypothesis, research and analysis the target damage coordinate law, estimated the average number of fragments hit the target; According to the related parameters of fragment dispersion area and target intersection, calculating the target damage probability. According to the design model, and gives out the fragment of target damage probability distribution of simulation results.