A syringe (10) is provided with a needle (12) , a body (14), and a protection device (20). The protection device (20) includes: an inner cylinder (42) which is rotatably mounted to the body (14) and which has a protrusion (76); and an outer cylinder (40) which covers the needle (12) and the inner cylinder (42) before a puncture, retracts and exposes the needle (12) during the puncture and advances and covers the needle (12) after the puncture. The outer cylinder (40) has: a guide passage (54) which guides the protrusion (76) and rotates the inner cylinder (42); and a restriction section (63) which, when the protrusion (76) has moved to a predetermined position in the guide passage (54) after a puncture , restricts the retraction of the outer cylinder (40).