In recent years, the need for high efficiency and low emission power generation systems has made much attention to the use of fuel cell technology. The solid oxide fuel cells due to their high operating temperature (800 ℃ -1000 ℃) are suitable for power generation systems. Two-component gas flow (H2 and H2O) in the porous media of solid oxide fuel cell’s anode have been modeled via lattice Boltzmann method; molecular distributions of the components are evaluated and the concentration voltage drop is investigated. The results of voltage drop in different current densities are validated with previous studies. Then the effects of various parameters such as porosity and non-dimensional current density on the gas diffusion of H2 and H2O, and also the concentration voltage drop in the porous anode are evaluated. It is revealed that at a specific non-dimensional current density, reducing porosity causes increasing H2 concentration in anode and concentration voltage loss. To apply the CFD model, a computer program in MATLAB has been used.