A liquid jetting apparatus receives delivery of liquid from a liquid delivery system including a delivery system-side terminal. The liquid jetting apparatus includes a apparatus-side terminal, a contact sensing portion and a remaining level sensor portion. The apparatus-side terminal contacts the delivery system-side terminal when receiving delivery of liquid from the liquid delivery system. The contact sensing portion supplies a first electrical signal to the apparatus-side terminal to sense contact between the apparatus-side terminal and the system-side terminal. The remaining level sensor portion supplies a second electrical signal different from the first electrical signal to the apparatus-side terminal to sense a liquid volume in the liquid delivery system.