PURPOSE: To provide a protector which can store a cannula in the protector easily and surely even if a tape or absorbent cotton adheres to a blade piece.

CONSTITUTION: A protector is adapted to store a used cannula of a detention needle with a blade comprising a cannula, a hub with a blade and a flexible tube. The protector includes a pair of opposed hinge pieces 2, 3 and a hinge base part 4 for connection the same in such a manner as to be opened and closed. A through hole 5 for passing the flexible tube is formed on the hinge base part 4, and the protector further includes a hinge part 1 where a groove 6 for loosely fitting a blade piece of a hub between the hinge pieces 2, 3, an opening and closing operation part 9 formed by a projection piece projected from the hinge base part 4 in the opposite direction to the hinge piece, an upper cover 12 connected to the piece 2 and a lower cover 13 connected to the hinge piece 3, wherein an upper click 14 is formed on the inner surface of the tip of the upper cover, a lower click 15 is formed on the inner surface of the tip of the lower cover, and when both clicks are engaged with each other, the upper cover 12 and the lower cover 13 are bound not to be opened.