The invention relates to a methanation process for gasification by an entrained-flow bed and aims at the problem that the existing methanation process is complicated in process, difficult to adjust, high in equipment manufacturing difficulty and high in operation cost when the amount of a circulating gas volume is large. According to the technical scheme, the process comprises the following steps of dividing a raw material gas from an upstream into two strands A and B which respectively enter two high-temperature reaction sections connected in parallel to be subjected to high-temperature reaction and heat recovery; dividing each strand of synthesis gas after heat recovery into two strands, namely strand A1 and strand A2, strand B1 and strand B2; cooling the strand A1 and the strand B1 separately by a boiler feed water water-preheater, then mixing and supercharging to 3.06-3.12Mpa through a compressor, and then equally dividing the mixed gas into two strands which respectively return to the high-temperature reaction sections connected in parallel to supply gas as the circulating gas; mixing the strands A2 and B2 of synthesis gas and directly feeding the mixed gas to a low-temperature reaction section to have a reaction to obtain qualified natural gas. The methanation process is simple, simple in temperature control and system regulation, and good in reliability, and meets the large-capacity circulating requirement.