Methoxypolyethylene glycols (mPEG) was first modified with succinic anhydride to obtain carboxylic acid terminated mPEG(mPEG⁃COOH). Epoxy resin emulsifier was fabricated by mixing the mPEG⁃COOH with epoxy resin, and the stable aqueous epoxy resin emulsion was obtained by phase inversion technique. The emulsifier structure, particle size distribution and the emulsion stability were characterized by infrared spectroscopy, high performance liquid chromatography and particle size analyzer. The effects of the molecular weight of mPEG, the type of epoxy resin and the emulsifier concentration on emulsion stability were carefully studied. The results showed that aqueous epoxy emulsifier and waterborne epoxy emulsion were successfully prepared. The aqueous epoxy emulsion has a particle size distribution of 0.8~1.5 μm and good emulsion stability. The obtained cured films by reacting the emulsion and amine curing agent at room temperature showed good water resistance and pollution resistance. Its water absorption rate and water loss weight loss rate were 0.35% and 0.25%, respectively.