An emitter that is arranged on an inner wall surface of a tube through which an irrigation liquid flows, the emitter being arranged at a position that corresponds to a discharge opening that communicates between the inside and outside of the tube. The emitter is for quantitatively discharging from the discharge opening the irrigation liquid inside the tube and has: a water intake part that is for taking in the irrigation liquid a discharge part that is for discharging the irrigation liquid and a flow path that connects the water intake part and the discharge part and through which the irrigation liquid flows. Further, an inner wall surface of the flow path is constituted by a composition that includes an antimicrobial agent and includes a resin or rubber.