The blade (52) of a puncture needle (30) provided to a puncture device (10) has first to third ridge lines (71-73) each having one end intersecting each other at the same intersection point (56). The other end of the first ridge line (71) terminates at the blade point (51). The other end of the second ridge line (72) terminates at a side surface of the puncture needle (30), the side surface being located closer to the base end of the puncture needle (30) than the intersection point (56), and the other end of the third ridge line (73) terminates at a side surface of the puncture needle (30), the side surface being located on the side opposite the other end of the second ridge line (72) at a position closer to the tip of the puncture needle (30) than the other end of the second ridge line (72).
