A blood sampling syringe includes a tube body, a pressing element, a first spring, a needle holder, a second spring, and a cover. The pressing element is formed with a plurality of abutting posts for abutting against the inclined engaging portions of the base part of the needle holder. The sliding channel and the side wall formed on the inner wall of the tube body are provided to clamp or release the needle holder. The first spring and the second spring disposed in front and rear of the needle holder make the needle holder to remain in the tube body even a needle is ejected, which allows a user to operate by a smaller force more safely.
