Aiming at fragment parameters optimization design problem of fragmenting warhead, in this paper, the fragment flying characteristics as well as the impact and penetration behavior were analyzed. Based on the overall and local analysis of the overload damage of the target board, it put forward the double target damage criterion of the energy consumption of the fragment and the kinetic energy per unit area to the target board, and established parameter optimization analysis model of warhead fragment. At last it estimated the energy consumption to the thin plate target and the damage probability by introducing the genetic algorithm. It showed the model could effectively analyze fragment length, diameter and velocity influence on the thin plate target. The research results can provide reference for optimization design of warhead fragment.