The effect of propane addition to the feed of methane aromatization process was studied both thermodynamically and experimentally. Thermodynamic equilibrium calculations were performed within temperature, pressure, and CH4/C3H8 molar ratio ranges of 673-873 K, 1-10 bar, and 0-20, respectively, considering different constraints according to two alternative reaction network models. Experimental evaluations were conducted in a fixed-bed reactor over Zn/HZSM-5 catalyst under different operating conditions. Methane formation showed an induction period of about 4 h on stream. Aromatic yield slightly increased with increase of methane concentration in the feed. Experimental results showed the best agreement with the thermodynamic model based on a proposed mechanism of methylation of propane-derived aromatics by methane, giving equilibrium methane conversions of about 1% under the above conditions. Both thermodynamic and experimental results revealed that in the presence of propane cofeed, the contribution of methane to the overall reaction is negligibly small on a net basis.