Abstract: This paper presents the many kinds of synthesis methods of Dimethyl Fumarate.The reation condition is investigated in detail with p-to-luenesulfonic acid,Thiourea as a catalysts and Maleic anhydride,Methanol as the reaction materials.The affection law of synthetic reaction is also discussed.Optimization technoloyical condition is obtained.The production yield reachs 92% with Thiourea 1.6 g,p-to-luenesulfonic acid 0.3 g,Malec anhydride 10.0 g,Methanol 20.0 g and reaction time 3 hours.