A puncture device that reliably acts on the target body site is proposed. The puncture device includes a luminal puncture body 2 having a projection opening 2a on the side surface; a tube 3, accommodated in the puncture body 2, having an acting part 3a that acts on the inside of the body; and a leading means 4 for projecting the acting part 3a of the tube 3 towards the side from the projection opening 2a. The leading means 4 includes a wire 5 inserted in the tube 3, and a moving means 6 for moving the wire 5 in the length direction of the puncture body 2, the moving means 6 adjusting the moving amount of the wire 5 to project the wire 5 from the projection opening 2a. The acting part 3a of the tube 3 can be projected by the projection of the wire 5.