Syntactic foams are hollow particle filled composites, which are finding applications in weight sensitive aircraft, marine and spacecraft structures. In the present study glass hollow particle filled vinyl ester matrix syntactic foam composites are studied for the effect of high strain rate loading on the failure characteristics. Syntactic foams with two different glass microballoon types, having 220 and 460 kg/m 3 densities, were used in volume fraction of 0.6 in the foam structure. Both particle types have nearly the same average diameter, leading to thinner walls in lower density particles. The high strain rate testing was carried out using a split-Hopkinson pressure bar by which strain rates in the range of 10 3 were attained. In composites containing thin walled particles the micro-CT scan images showed particle crushing in the surface layer as well as composite densification. Shear cracks were the macroscopic fail mode in the specimens. In the specimens containing thicker walled particles the specimen fracture behavior transitioned from shear cracking to crack initiation and propagation in the direction of loading as the strain rate increased. These results can help in optimization of energy absorption at different strain rates.