Advanced composite materials are widely used as marine current turbines due to their high strength-to-weight ratios and excellent resistance to corrosion. A novel manufacturing approach similar to filament winding has been developed and is able to produce the Composite Material Marine Current Turbines (CMMCTs) that have significant advantages over traditional designs. This paper presents numerical results investigating the performance of ducted CMMCTs. The numerical approach was performed using CFD in a free stream of water with various hydrodynamic flow conditions. The investigation results provide an insight into the hydrodynamic design and operation of CMMCTs.