The invention relates to boiling-water-resistant waterborne ink applied to PVC printing, which includes, by mass, 38-46 parts of an aqueous polyurethane-acrylic resin emulsion, 35-45 parts of deionized water, 5-8 parts of a styrene-acrylic emulsion, 7-17 parts of a pigment, 1-2 parts of ammonia water, 1-2 parts of a defoamer, 2-3 parts of an additive, and 2-5 parts of nano-fluorescent powder. The pigment is a modified pigment which is modified through the steps of: mixing a common pigment, potassium hexatitanate whiskers, glass flakes, titanium dioxide, barium sulfate and ethanol, adding the mixture to a container with a stirring unit, and stirring the mixture for 15-25 min; and then adding sodium m-carboxylbenzenesulfonate, and uniformly stirring the mixture to prepare a micro-emulsion; moving the micro-emulsion into a vacuum ball milling tank, and placing the ball milling tank in a ball mill to perform planetary vacuum ball milling; and relieving pressure, discharging the materials, and drying the materials to prepare the modified pigment. The boiling-water-resistant waterborne ink is high in color fastness to light, has high adhesion force, is low in viscosity and is good in water resistance.