The invention belongs to the field of carbon dioxide emission reduction and carbon dioxide conversion, and relates to a method for converting greenhouse gases into high value-added CH4 and CO. The invention is characterized in that media block electric discharge to activate CO2 and H2 molecules and form uniformly distributed nonequilibrium plasmas, hydrogenation is carried out on activated species on a catalyst arranged in a plasma reactor, and CH4, CO, CH4 and CO mixtures are selectively generated; and the proportion of reaction gases of CO2 and H2 is not fixed. The method can convert the greenhouse gas CO2 into high value-added CH4 and CO. The method does not have special requirements or limits on the source and composition of the gas, thereby having universality on CO2 and H2 gases with various components. The technical method can be applied to the hydro-conversion of CO2 with high concentration, and can also be used for the hydro-conversion of CO2 in industrial gasses with low concentration and underground coal gasified gas.