Abstract: A process was designed and simulated by Aspen Plus for the production of synthetic natural gas (SNG) from municipal solid waste (MSW) gasification, with O₂ and steam as gasifying agents. The influences of O₂ to MSW equivalent ratio (ER), steam-to-MSW mass ratio (m(S)/m(MSW)), methanation temperature and methanation pressure on the CH₄ concentration in SNG, lower heating value (LHV) of SNG and energy conversion efficiency were analyzed in detail. With the increase of ER, m(S)/m(MSW) and methanation temperature, the CH₄ concentration, LHV of SNG and energy conversion efficiency were decreasing, respectively. And a higher methanation pressure was in favor of CH₄ content, LHV and energy conversion efficiency. When the ER, m(S)/m(MSW), methanation temperature and pressure were 0.35, 0.5, 250 ℃ and 0.5 MPa separately, the quality of produced SNG could meet the requirements of two-class NG of GB 17820-2012.