The effects of the initial feed composition, temperature and pressure and input methanol/steam ratio on the equilibrium conversion were examined for the methanol steam reforming. The two reaction system was analyzed: CH3OH + H2O double left right arrow 3H(2) + CO2, CO2 + H-2 double left right arrow CO+ H2O. The results were presented in form of plots. These results are useful for the correct choice of the parameters of the process to prevent poising fuel cell and obtain the high efficiency. Increasing attention that is paid to the catalytic production of high-purity hydrogen by steam reforming of methanol is caused by its application as fuels in fuel cells (PEMFC) for on-board power generation for vehicles. The most widely used catalysts for this reaction are copper containing catalysts that require temperatures about 550 K. The fuel cell is highly sensitive to poisons, especially carbon monoxide, which even very low concentration has a detrimental effect on its performance. The thermodynamic analysis of the methanol steam reforming has been done.