A fluidic diode (FD) cascading concept was proposed and analyzed to determine the effect on the oscillating water column (OWC) wave energy converter performance. The FD, coupled with a twin-turbine, can improve energy conversion. The performance of the FD is given by the diodicity, which is the ratio of pressure drops. In this paper, the concept of cascading of FD is numerically investigated by solving the three-dimensional Reynolds Averaged Navier Stokes (RANS) equations. The commercial computational fluid dynamics (CFD) tool ANSYS FLUENT 16.1 is used for the present investigation. The present study showed that the cascading increased pressure drops in both directions, which reduces the diodicity compared to the base model. The performance of the twin turbine with cascade FD underperformed than the twin-turbine without FD There are various FD models proposed for various engineering applications. For example, they find applications in the nuclear power plant, the microfluidic, and chemical industry where there is a need to prevent the reverse flow . Incident wave Air turbine model.