The present invention provides an isocyanate group terminated prepolymer aqueous dispersion (A) that is composed of water and an isocyanate group terminated prepolymer (a) dispersed in the water, whose content in the (A) is in a range of 60 wt % to 85 wt %, wherein the (A) optionally contains a-surfactant in a range of 0 wt % to 10 wt % based on a weight of the (a), and a solvent in a range of 0 ppm to 5,000 ppm based on the weight of the (a). The present invention also provides a polyurethane resin aqueous dispersion (B) that is composed of a polyurethane resin (b), whose content in the (B) is in a range of 20 wt % to 65 wt %, wherein the (b) is obtained by a chain extension reaction of the (A). The present invention is capable of providing a polyurethane resin aqueous dispersion having excellent storage stability. The aqueous dispersion can be used in a polyurethane resin sheet material, a paint, an adhesive, a tackiness agent, or a fiber-treating agent that has less flammability, a high level of safety to the human body, and environmental friendliness, and is effectively applied in a leather-like polyurethane resin sheet material in which migration is prevented.