A puncture device includes a puncture member having a puncture needle 31 for puncturing a living body tissue, a shaft portion, and a connection portion for connecting the puncture needle 31 and the shaft portion to each other. The puncture needle 31 includes a needle main body 311 for puncturing the living body tissue, and an extension needle 316 provided for movement relative to the needle main body 311 along a longitudinal direction of the needle main body 311 and configured to puncture the living body tissue. The puncture device includes, as extension means for moving the extension needle 316 in a direction toward the distal end of the needle main body 311 with respect to the needle main body 311 to extend the puncture needle 31, a pusher for pushing the extension needle 316 to move in the direction toward the distal end of the needle main body 311.
