PURPOSE: To obtain a room-temperature-curing aqueous resin dispersion having a film Tg in a specified range, excellent water resistance and good contact by emulsion-polymerizing a radical-polymerizable monomer in the presence of an epoxy resin and an oil-soluble polymerization initiator in an aqueous medium.

CONSTITUTION: A radical-polymerizable monomer is emulsion polymerized in an amount of 40-80 pts.wt. in the presence of 20-60 pts.wt. epoxy resin and an oil-soluble polymerization initiator in an aqueous medium to obtain a room- temperature-curing aqueous resin dispersion which can give a film of a Tg of 10 to -40°C. As the radical initiator is used, this composition has good water resistance and good contact as compared with a conventional aqueous resin dispersion being a combination with an epoxy resin. Further, it can be smoothly cured with an epoxy resin into a highly heat-resistant product and has performance equivalent to that of a solvent-based chloroprene adhesive.