Abstract: Taking a non-streamline submerged body as a model, its drags under the natural condition and artificial ventilated condition are numerically simulated using mixed homogeneous flow theory and realizable turbulence model. Numerical simulation of a streamline body’s drag with the above method is compared with approximate formula calculation and the applicability of numerical method is verified. The regulations of the drags of non-streamline submerged body under the natural condition and artificial ventilated condition are found. The result shows that the drag of non-streamline submerged body under natural condition is greatly increased compared with that of streamline body, and the pressure drag is the main component. However, after artificial ventilation and the supercavity is formed, the drag is greatly decreased. The viscous drag can be ignored when the cavity number is small enough.