The present invention relates to a high efficiency of methanol production method capable of reducing the emission of carbon dioxide, still more detail with the water vapor and gas in the reaction feed was converted to methane for C _{2 +} hydrocarbons contained in the natural gas over a catalyst mixed gas a third step of the synthesis of methanol over a first step of manufacture, a second step of producing hydrogen, carbon monoxide and carbon dioxide, the syngas molar ratio is adjusted from the mixed gas, the catalyst used for the synthesis gas as a raw material for as in OCCURS step, unreacted synthesis gas that is injected into the suitable amount of carbon dioxide in one of the reforming reactor and the methanol synthesis reactor of the third stage of the second step, or injection by dispensing both locations, and exits the third-stage methanol synthesis process back to the second stage process and recycled to the same time only by a three-step process or a third process step re-use as a raw material He said, by the heat of the part of the unreacted synthesis gas is used as combustion gas for a heating for supplying the heat of reaction required in the second step with a gas and, after combustion is discharged from the heating by the hot gases groups a series of heat exchange to efficiently recovered by permitting use of a reduced amount of natural gas relates to a high efficiency of methanol production method capable of maximizing the carbon efficiency and thermal efficiency of the overall process.