Steven test for PBX-2 explosive was made by using little blunt warhead,pin shape warhead and plane projectiles of 2.0 kg. The pressure change was measured by manganin pressure gauges and poly vinylidena fluoride(PVDF) piezofilm stress gauge. Ignition process was analyzed by high-speed motion pictures. The reaction overpressure of explosive was obtained by blast pressure gauges. Reaction for explosive was analyzed under different shape warhead impacts in Steven test. The results show that explosive reaction is more intensive because of strong shear band under plane impact in Steven test,and reaction degree for PBX-2 explosive is higher under plane warhead.