In order to develope a device that could disrupt explosive components quickly and easily, a special shaped charge structure was studied. AUTODYN two-dimensional program was used to simulate the forming progress of water jet. The speed of water jet with different thicknesses of explosive was obtained. The results show that that the device can generate a water jet. The water jet tip velocity and average velocity increase with thickness of explosive. And, when the thickness of explosive range from 4 to 6 mm, the water jet tip velocity ranges from 861 to 1282 m·s^-1 and the average water jet velocity range form 393 to 571 m·s^-1. The water jet can disrupt explosive objects safely at this velocity range in theory.