To provide a curable water-based resin composition which cures as it forms vinyl bonds and enables the formed vinyl bonds to be cationically or radically polymerized and can also photo-cure.

This curable water-based resin composition is prepared by copolymerizing 0.1-99.9wt.% of a primary hydroxyl-containing monomer, 0.1-99.9wt.% of a monomer containing a ketone group having two adjacent carbon atoms (where at least one hydrogen atom bonds to at least one carbon atom) and 0-99.8wt.% of vinyl monomers other than above-stated monomers.