Drip detection device

A drip detection device (1) is provided with: a cylindrical drip chamber (11) for receiving a droplet (13) therein dropped from a bottom end of a nozzle (12), the nozzle (12) being inserted in the drip chamber (11) from the top thereof; and a photo-interrupter (5) having one or more light-emitting elements (52) for radiating light and two or more light-receiving elements (51) for receiving the light; the one or more light-emitting elements (52) and the two or more light-receiving elements (51) being disposed in opposing or substantially opposing positions with the drip chamber (11) interposed therebetween, two or more light paths (53) connecting the one or more light-emitting elements (52) and the two or more light-receiving elements (51) being positioned lower than the bottom end of the nozzle (12), and at least one of the light paths (53) leading to the light-receiving elements (51) being non-parallel to the other light paths (53) in plan view and in front view.