A liquid administration apparatus comprises: a cylindrical body which has a bottomed cylindrical shape with a bottom portion on a distal end portion and inside of which is filled with a liquid a needle tube which has a sharp distal end side needle tip on at least the distal end out of the distal end and a base end, is provided on the distal end side of the cylindrical body and is communicable with the cylindrical body a gasket which is capable of sliding inside the cylindrical body an operational member for performing a pressing operation in which the gasket is pressed towards the distal end direction thereby discharging the liquid from the needle tube, and which has a first plunger portion that is connected to a base end side of the gasket and a second plunger portion that is disposed on the base end side of the first plunger and a locking means for maintaining the positional relationship between the first plunger portion and the second plunger portion. The operational member is capable of taking on a first state in which, while the positional relationship is maintained by the locking means, the gasket is pressed to the movement limit where the gasket comes in contact with the bottom portion, and a second state in which maintenance of the positional relationship from the first state is cancelled and the second plunger portion is moved towards the distal end direction with respect to the first plunger portion.Linvention concerne un appareil dadministration de liquide, qui comprend : un corps cylindrique qui a une forme cylindrique inférieure ayant une partie inférieure sur une partie extrémité distale et à lintérieur duquel est introduit un liquide un tube daiguille, qui a une pointe daiguille pointue côté extrémité distale sur au moins lextrémité distale parmi lextrémité distale et une extrémité de base, est disposé sur le côté extrémité distale du corps cylindrique et peut communiquer avec le corps cylindrique un joint qui est apte à coulisser à lintérieur du co
