The clamp band system is a typical locked and separated device of the launch vehicle (LV) / the spacecraft (SC), and its release-separation process is one of the important factors that affect the LV/SC separation movement. A nonlinear spring-damper model was employed to describe the contact-impact behavior between the V-segment of the clamp band and the LV/SC interface, and lumped mass method was used to depict the clamp band. By using ADAMS, a dynamic model of the clamp band system was established. The simulation results show that the impulse of the explosive bolts and the stiffness of lateral-restraining springs have significant effects on the clamp band dynamic envelope. The shock of the satellite-vehicle separation is very vulnerable to the clamp band pretension and the friction coefficient between the V-segment and the LV/SC interface.