NOVELTY - A simultaneous production of methanol and synthetic natural gas involves pre-processing greater than or equal to 1 coke oven gas, adjusting hydrogen/carbon rate by adding greater than or equal to 1 carbon containing gas to pre-processed coke oven gas, compressing and desulfurizing arising mixed gas, and implementing methanol synthesis reaction, separating arising methanol synthesis reaction product into high methanol flow and low methanol flow, and subjecting low methanol flow to methane synthesis reaction in 2 or 3 methane synthesis reaction devices connected in series.    USE - A simultaneous production of methanol and synthetic natural gas (claimed).    ADVANTAGE - Carbon dioxide discharge amount is reduced, running cost is low and the method is economical and environment-friendly.    DETAILED DESCRIPTION - A simultaneous production of methanol and synthetic natural gas involves pre-processing greater than or equal to 1 coke oven gas, adjusting hydrogen/carbon rate by adding greater than or equal to 1 carbon containing gas to pre-processed coke oven gas, compressing and desulfurizing arising mixed gas, and implementing methanol synthesis reaction, separating arising methanol synthesis reaction product into high methanol flow and low methanol flow, subjecting low methanol flow to methane synthesis reaction in 2 or 3 methane synthesis reaction devices connected in series, and producing synthetic natural gas by separating water from arising methane synthesis reaction product. An INDEPENDENT CLAIM is included for a plant for carrying out simultaneous production of methanol and synthetic natural gas comprising greater than or equal to 1 coke-oven-gas pre-processing unit, greater than or equal to 1 carbon dioxide (CO2) acquisition unit, greater than or equal to 1 compression and desulfurization unit, greater than or equal to 1 methanol synthesis unit, greater than or equal to 1 supercold-separation unit and case in which inlet port of coke-oven-gas pre-processing unit is connected with greater than or equal to 1 coke-oven-gas exit of coker, inlet port of CO2 acquisition unit is connected with flue gas exit of coker, exit of CO2 acquisition unit and exit of coke-oven-gas pre-processing unit are connected with inlet port of compression and desulfurization unit through mixing apparatus, exit of compression and desulfurization unit is connected with inlet port of methanol synthesis unit, exit of methanol synthesis unit is connected with inlet port of methane synthetic unit through purifier, and exit of methane synthetic unit is connected with inlet port of supercold-separation unit by the case.