The Hydrodynamic performance of the High-Speed Displacement vessel with and without a Hull Vane (HV) was systematically investigated using the Computational Fluid Dynamics (CFD) software Star-CCM+ based on RANSE solver. Hull Vane is an Energy-Saving device (ESD), invented by Dr. Peter Van Oossanen and introduced by Hull Vane BV company to reduce the residuary component of ship resistance and ship motions in waves. HV is a hydrofoil wing transversely fixed at bottom of the transom hull which alters the flow around the stern thereby reducing the resistance of the vessel. The Hull Vane alters the flow immediate of the transom and creates a low-pressure region on the top surface of the HV. This low-pressure region interacts favourably with stern wave system, thereby reduces the resistance which further results in the most desirable trim control. Though research has been carried out in the design of the Hull Vane, in this article, the effect of Position in the X-direction, and Z-direction of the HV, Span, Chord, and Angle of the HV on the wave-making component of resistance has been analyzed. The CFD model is validated with experimental model test results for both the bare hull and Hull Vane cases. With the addition of the Hull Vane, a residuary resistance coefficient reduction of 20.81% has been observed at the operating Froude number.