Wide bandwidth and high data transfer rates are essential advantages of optical telecommunication networks. Full exploitation of the benefits of optical communications requires a fully optical network. All-optical circuits are one of the main alternatives to eliminate the limits of electronic circuits and provide high-speed processing systems. This study aims to design an Majority Gate based on the Nonlinear Kerr Effect. The proposed structure includes a directional COUPLER with nonlinear rods. In the proposed structure, a nonlinear directional COUPLER is used to transmit the phase of the input signal. Also, input connections are optimized to prevent the return of light along the structure. To evaluate the operation of the proposed structures, PWE and FDTD methods are used. The effect of some parameters variation on the output power has been investigated, proving the robustness of this designed structure of Majority gate against process variation. In this simulation, the proposed structures' switching power is 3 W and the bit rate is Tbits/s.