In order to explore dynamics modeling and control of supercavitating vehicles, the memory effect of the cavity and its influence on shape of cavity were discussed based on the principle of cavity expansion independence. The cavitator orientation effect and cavity floatation were taken into account in computing the hydrodynamic forces of all parts of the supercavitating vehicle. Efficiency of the fin as the fin immersion depth changes while the vehicle is traveling underwater was investigated. A more precise nonlinear dynamics model of supercavitating vehicle was established. Robust pole placement controller was designed after exact input-output linearization. Simulation results indicate that stabilization control of the close-loop system with special initial disturbance is achieved.