The present invention relates to a curable resin composition for use in water-based coating materials which includes as essential components an emulsion polymer (A) containing tertiary amino groups obtained by carrying out emulsion polymerization of a vinyl monomer containing a tertiary amino group with another copolymerizable vinyl monomer in a water-based medium, and a compound (B) containing, at least, an epoxy group and a hydrolyzable silyl group, with this composition preferably also including a water-based compound (C) obtained by adding a neutralizing agent to a vinyl polymer (I) containing acidic groups and/or tertiary amino groups so as to neutralize at least 10% of the acidic groups and/or the tertiary amino groups, and then dispersing or dissolving in water, and/or a compound (D), which is not included in compound (B), and contains hydrolyzable silyl group and/or a silanol group. The coating material provided by the composition of the present invention is curable at ambient temperatures and demonstrates excellent coating properties. Moreover, the cured coating obtained from the composition of the present invention offers superior resistance to weathering, solvents, chemicals and water, and is not problematic with respect to conservation of the environment.