A needle assembly 1 includes a hub 4 retaining a cannula 3, a protective unit 5 advancing and retracting to surround the forward end of the cannula 3, and a cylindrical portion 6 surrounding the outer periphery of the protective unit 5； the protective unit 5 has a construction in which a protective cover 7 protruding from and retracting into the cylindrical portion 6 is formed integrally with a spring portion 8 so as to be in series therewith, with the hub 4 and the cylindrical portion 6 being coupled together to form a hub member.
