Foreign object damage(FOD) often occurs while engine blades are working.The damage due to different foreign object impacting is different.The energy balance model and the fundamental hydrodynamics were used to analyse the impact force for soft body and hard body impacting on the blades. Numerical simulations of soft body and hard body impacting on the blades were done in the LS-DYNA. Gelatine and sandstone were respectively used as soft body and hard body in the simulations.The results suggest that the amplitude value of the impact contact force for sandstone impacting is bigger than the one for gelatine impacting with the same initial impacting energy and the same impacting velocity and the same impacting angle.But its duration is shorter than the one for gelatine impacting. Sandstone and blade gain the most strain energy at the moment of impacting.Because of the gelatine’s rheology during the impacting, the local damage for blades due to gelatine impacting is smaller than the one due to sandstone impacting.