To provide an aqueous dispersion of a polyurethane resin, excellent in heat resistance or repulsive elasticity of its dried film.

This aqueous dispersion of a polyurethane resin consisting of (A) a polyurethane resin having ≥2 polymerizable unsaturated groups selected from (meth)acryloyl, (meth)allyl and propenyl groups at its molecular side chain and an aqueous medium is obtained by dispersing (A0) a prepolymer having an isocyanate terminal obtained by reacting (a) an organic polyisocyanate, (b) a polyol and (c) a compound having ≥2 polymerizable unsaturated groups selected from ≥2 hydroxyl, (meth) acryloyl, (meth)allyl and propenyl groups in an aqueous medium and then further performing a chain-extending reaction.