A dispenser that can prevent leakage of contents from a nozzle tip when stopping discharging the contents is provided. A dispenser 1 comprises: a syringe body 10 that has a filled space M of contents, and has a discharge hole 45a at a tip thereof； a plunger 20 that is slid in the syringe body 10 by application of a pushing force, to discharge the contents in the filled space M from the discharge hole 45a； and a piston 30 that is formed of an elastic material and located at a tip part of the plunger 20, wherein a gap G is formed between an inner peripheral surface of the syringe body 10 and an outer peripheral surface of the piston 30, when the plunger 20 is pushed, the piston 30 deforms to narrow the gap G, and a back leakage risk (= (gap (G) area / final discharge hole area)) after the deformation of the piston 30 is 0 or more and less than 1.
