The invention discloses a preparation method of a Mn-Ce methane combustion catalyst. The method comprises the following steps: (1) mixing a manganese-based salt Mn<2+> aqueous solution and a potassiumpermanganate (KMnO4) solution, adding an alkali solution and keeping pH of the mixed solution acidic; (2) performing aging treatment on the mixed solution, and performing filtering to obtain a MnOx solid; (3) mixing the MnOx solid and a cerium salt Ce<4+> aqueous solution, performing a hydrothermal reaction, and performing filtering to obtain a MnCeOx solid; and (4) drying the MnCeOx solid, and performing calcination to obtain the Mn-Ce catalyst containing KyMn8O16. The method provided by the invention can obtain the catalyst with better catalytic activity in methane combustion, and the catalyst has stronger thermal stability and sulfur resistance; and compared with other current preparation methods of the Mn-Ce catalyst, the preparation method provided by the invention has a simple preparation process, shorter total time in the preparation process, a high methane conversion rate of the catalyst, and better industrial application value.