An application device (1), which applies a liquid with a viscosity in the range of 0.05 - 4 Pa.s on an absorbent article product, semi-finished product or raw material that is being conveyed by a conveyance device (3), is equipped with: a tank (11), which holds the liquid； a nozzle (13), which applies the liquid on the product, semi-finished product or raw material； a pump (17) that supplies the liquid inside the tank to the nozzle via a tube (15)； and a liquid scale disposed in the tube between the pump and the nozzle for detecting the volume of liquid supplied from the pump to the nozzle.
