Abstract: A new method for the calculation of Gibbs free energy of formation of zeolites is introduced, which is based on the assumption that the Gibbs free energy of formation of zeolites is equal to the sum of the Gibbs free energy of all oxide components and the Gibbs free energy of reaction between the exchange ion oxide and alumina.The Gibbs free energy values of many zeolites were calculated.The results showed that the deviation between the experimental value of ΔG⁰_f of zeolite formation and those calculated by this method was less than 1%, and the molar Gibbs free energy of formation of hypothetical ［SiO₂］ unit in each zeolite was below that of silica of all phase states.The presence of crystal water in zeolite was in favor of increasing the thermodynamic stability of zeolite.