To simply and surely cover a needle after use and prevent leakage of blood from an opening in a protector.

The protector 16 has a tube 29, a shutter 32 which slides from a first flat surface portion 36a of the tube 29 to close an upward opening 30, and a guide groove 50 which leads the shutter 32 to the upward opening 30 from the first flat surface portion 36a. A blood sampling needle 14 to which a tube 12 is connected, is contained in the tube 29. The tube 29 is equipped with an annular seat surface 60 which abuts on the blood sampling needle 14 from the upward opening 30 and contacts the blood sampling needle 14 when the tube 12 moves. The upward opening 30 inclines in relation to the first flat surface portion 36a. The shutter 32 has elasticity and closes the upward opening 30 while carrying out elastic transformation according to a gradient in a slide direction.