The liquid-administering instrument is provided with: a tube that is filled with the liquid a needle shaft that has a front end needle tip, is provided on the front end side of the tube, and can communicate with the tube a gasket capable of sliding inside the tube an operating member for performing the pressing operation of pressing the gasket toward the front end and discharging the liquid from the needle shaft a restricting member capable of restricting the pressing operation and a cover member capable of moving to a first position in which the front end needle tip is covered and to a second position in which the front end needle tip is exposed. Protrusions are molded to protrude from the restricting member. Grooves into which the protrusions are inserted are formed on the operating member. The grooves have a longitudinal groove formed in the same direction as the direction of operation during the pressing operation and a transverse groove, which communicates with the longitudinal grooves and is formed in a direction that is orthogonal to the direction of operation. When the cover member is in the first position, the protrusions are located in the transverse groove and restrict the pressing operation. When the cover member moves from the first position to the second position, the protrusions move, in conjunction with said movement, from the transverse groove to the longitudinal grooves, thereby allowing the pressing operation.Linvention concerne un instrument dadministration de liquide comprenant : un tube rempli dun liquide une tige daiguille dotée dune pointe dextrémité avant située sur le côté dextrémité avant du tube et pouvant communiquer avec ce dernier un joint pouvant coulisser à lintérieur du tube un élément fonctionnel permettant dappliquer une pression sur le joint vers lextrémité avant et chasser le liquide de la tige daiguille un élément de restriction permettant de restreindre lopération de pression et un élément de capuchon pouvant se déplacer
