Abstract: A process for vapor-phase synthesis of N-mehtyl-2-pyrrolidone (NMP) from γ-butyrolactone (GBL) and aqueous methylamine over ZSM-5 molecular sieve was studied. The effects of liquid hourly space velocity (LHSV), reaction temperature, silica to alumina ratio of ZSM-5 molecular sieve and molar ratios of raw materials on the yield of NMP were investigated. Test results showed that using ZSM-5 molecular sieve catalyst with silica to alumina ratio of 120, under the conditions of molar ratios of methylamine: GBL: water was optimized to 1.5: 1.0: 30, LHSV of 0.5 h-1, under atmospheric pressure and a reaction temperature of 300 ℃, the yield of NMP could reach about 99%.