An aluminum chelating agent-based latent curing agent is provided that can rapidly cure thermosetting epoxy resins at relatively low temperatures. A method for producing the aluminum chelating agent-based latent curing agent is also provided that enables relatively facile control of the curing conditions therefor. The latent curing agent holds an aluminum chelating agent in a porous resin obtained by the interfacial polymerization of a polyfunctional isocyanate compound, and when the latent curing agent is incorporated in a curable epoxy resin composition for differential scanning calorimetric (DSC) measurement, the DSC exothermic peak temperature of the curable epoxy resin composition for DSC measurement that contains the latent curing agent that has been treated by immersion in a nonaqueous polar solvent can be brought to not less than the DSC exothermic peak temperature of the curable epoxy resin composition for DSC measurement that incorporates the latent curing agent that has not been subjected to the immersion treatment.