The invention relates to a method for preparing aqueous
epoxy resin curing agents, which comprises the following steps: firstly, uniformly mixing vulcabond,
dimethylolpropionic acid, terminal hydroxyl polymers,
bisphenol A, organic solvents and catalysts, preparing terminal
isocyanate polyurethane performed polymers through prepolymefization reaction, using
imidazole and
imidazole derivatives or pyrromonazole and
imidazole derivatives as terminal sealing agents for reaction, and finally, neutralizing the imidazole and the imidazole derivatives or the pyrromonazole and the imidazole derivatives to obtain the aqueous
epoxy resin curing agents. In the method provided by the invention, because both the sealing agents and the neutralizing agents can react with
epoxy resin, no existence of free components after curing is ensured, active -NCO released after the sealing removal can react with
carboxylic acid to reduce the hydrophilicity of a
system and can also react with the epoxy resin to increase the cross linking density of curing objects, the
toughening effect can be realized on the epoxy resin through the induction of the terminal hydroxyl polymers, and the
bisphenol A can be used for enhancing the compatibility of the curing agents and the epoxy resin and improving the integrated performance of the curing objects.