Abstarct: In this study, the effect of sea wave characteristics under certain conditions on the ground effect phenomenon in Persian Gulf has been investigated, that NACA4412 airfoil at height of 1 m above sea level at speed of 55.14 m/s over waves with a length of 12.64 meters and a height of 1 meter has been studied. For numerical analysis in this problem, two-phase flow is used to simulate waves and inlet velocity boundary condition for the waves is considered. The unsteady flow-dependent airfoil on the wavy water surface is numerically simulated by a computational fluid dynamics solver. Two-dimensional incompressible equations is solved by using the finite volume method and the k- SST turbulence model. The results show that due to the wavy shape of the sea level, the pressure changes under the airfoil are proportional to the change in altitude in the wave, which is followed by changes in the aerodynamic coefficients that are due to pressure changes and the oscillations of the coefficients are in the form of diagrams of the applied waveform. Changes in aerodynamic forces have occurred due to the formation of a convergent-divergent passage between the airfoil and the undulating surface of the sea water, which has caused a change in pressure. Graphs related to lift coefficients and drag coefficients and momentum due to the presence of convergent-divergent passage are a set of fluctuations and in the range of 0 to 4 degrees with increasing angle of attack, lift and drag force increases and also with increasing angle of attack The momentum decreases and the intensity of the oscillations increases.