To provide a water-based coating material capable of forming a coating film having good finished appearance, water resistance, scratch resistance and oil resistance on a plastic substrate, especially on a polyolefin resin under the forced drying condition at a relatively low temperature within a short time.

The water-based coating material contains an aqueous dispersion obtained by mixing and dispersing an aqueous emulsion of (A0) porous resin particles and (B0) a modified chlorinated polypropylene resin containing (b10) a chlorinated polypropylene and (b20) a maleic anhydride-modified chlorinated polypropylene produced by bonding maleic anhydride to a chlorinated polypropylene and an acrylic polymer-modified chlorinated polypropylene produced by polymerizing an acrylic monomer to a chlorinated polypropylene and/or a maleic anhydride-modified chlorinated polypropylene.