Abstract: A sheath for protecting and maintaining sterile a syringe needle and for preventing breakage of the needle during use is disclosed. The sheath is mounted on a syringe of the type used for introducing liquid medication into flexible bags for the administration of intravenous solutions, and serves to guide and protect the needle as it is inserted into the flexible inlet tube of such bags and to hold the needle and syringe in alignment during the injection of medication to prevent breakage of the needle. The syringe housing is formed with a boss, or hub, through which the needle extends, and the sheath is secured to this boss by means of an inwardly turned axial mounting collar. An end wall partially closes the protective sheath and abuts the closed end of the syringe housing to provide a relatively large contact area between these two elements to hold them in alignment. The annular collar frictionally engages the syringe body hub to securely hold the protective sheath in place.