The shock properties of C100 concrete are investigated by the gas gun planar impact technique. The manganin pressure gauge is used to measure the pressure-time curves of the samples. The physical quantities are all obtained by the Lagrange method. Moreover, it is observed from the measured pressure-time curves that the rate-sensitivity of dynamic response for C30 concrete is not negligible, showing marked stress relaxation and dissipation. The damage factor is introduced into the state equation. The material parameters in the Grüneisen-type equation of state are determined.