Abstract: Presents an assessment of the lethality capabilities of impact initiated reactive fragments and a dynamical testing technique for the energy release characteristics of reactive fragments. The energy release characteristics of three reactive fragments with various formulations were measured by ballistic experiments. The results showed that all three reactive fragments could undergo a rapid volatile chemical reaction and release great amounts of thermochemical energy under strong impact loadings. And the energy release efficiency of reactive fragments is markedly influenced by the impact velocity. The released chemical energy of reactive fragment reached about 5 times its kinetic energy at an impact velocity of 1500m/s, enhancing greatly its lethal capabilities.