Abstract: Based on the homogenous equilibrium flow assumption and Mixture model, the relative accelerating motion between the vehicle and the fluid was realized by considering the body force of fluid in moving coordinate and adding source into momentum function, at the same time, the flow speed at the inlet boundary was setted as a function of the time. Then the variation regularity of the nature supercavity hysteresis time and the pulse characteristic of the ventilated supercavity shape in the supercavitating vehicle accelerating process was obtained. The results show that as the velocity reached equality uniform status, the supercavity hysteresis time becomes shorter with the decrease of the acceleration; with the acceleration fixed, a shorter nature supercavity hysteresis time is observed when the velocity becomes larger; the supercavitating vehicle accelerating process causes the ventilated supercavity shape continuous pulse.