The shear device for explosive tablet was designed by ANSYS/LS-DYNA and the response character was studied using Φ20 mm×5 mm and Φ20 mm×9 mm PBX-2. The pressure change was measured by Manganin pressure gauges. Ignition process was analyzed by high-speed motion pictures. The reaction overpressure of explosive was gained by blast pressure gauges. Results preliminary show that height threshold decreases from 3.5~3.7 m to 3.0~3.1 m with explosive thickness increasing. The height threshold decreases when increasing explosive thickness in shear test for explosive tablet.