Abstract Supercavity shedding is a focus question closely related to the stability of supercavitating flows. It is an important factor in laying a solid foundation for implementing the controllability and maneuverability of supercavitating vehicles. The effects of gravity and angle of attack (AOA) on ventilated supercavity in water tunnel are modeled respectively. Based on these models combining with Logvinovich model, supercavity shedding after velocity disturbance is simulated. FFT (Fast Fourier Transform Algorithm) is used to analyze the frequency characteristic of ventilated supercavity based on the numerical results. The results show that the shedding frequency of supercavity is not related to the disturbance frequency as an intrinsic instability property after the disturbance for the given dynamics parameter and AOA, and the frequency approximately equals the pulsation frequency of the shape parameter of supercavity. The respective relations between the shedding frequency and the gas dynamics parameter, AOA are also presented.