The invention relates to a preparation method of a catalyst for methane tri-reforming to synthesis gas. The catalyst carrier is dipped in the first solution at first, and the first precursor is prepared by drying and roasting; the dosage of the solvent in the first solution and the soluble nickel salt is determined by the mass of the catalyst carrier; the first precursor is then dipped in the second solution and the invention is prepared by re-drying, roasting and deoxidization; the dosage of the promoter soluble salt and the solvent is determined by the mass of the catalyst carrier; the carrier is prepared by the co-deposition method and surface induced coating method; the prepared catalyst has high activity and stability; on the condition of the oxygen, the rate of conversion of the catalytic carbon dioxide is extremely close to the balance conversion. On the conditions of 850 DEG C, 1 atm, CH4:CO2:H2O:O2 is equal to 1:0.48:0.54:0.1 and GHSV is equal to 10080h-1, the rate of conversion of methane reaches 92.27 percent, the rate o conversion of the carbon dioxide reaches 78.91 percent. On the condition, the activity is not reduced after continuous operation for 50 hours.