The present invention is directed to a safety needle assembly having the high safety and high operability, comprising: a hub； a cannula； a collar； a protector； and a sheath. The sheath includes an opening of housing the cannula； a cannula fixing part of locking the cannula housed in the opening； an attachment part of rotatably supporting the sheath attached to the hub or the collar； and a protrusive stopper which a user pushes by a finger to pivot the sheath thereby to house the cannula in the opening of the sheath. Herein, the stopper is arranged at a vicinity of a central portion of the sheath in a longitudinal direction at the opposite side of the aperture of the opening, or arranged at a portion closer to a distal end side than the central portion of the sheath.
