A puncture device which can be made smaller in size and lighter in weight and a method for manufacturing the same are provided. A puncture device 1 is a device for transferring an active ingredient into a body through a skin. The puncture device 1 comprises a tubular housing H, a piston P slidably arranged within the housing H, and a conical coil spring 40 arranged within the housing H and providing the piston P with a biasing force. The piston P has a piston body 20 and a microneedle member 30 engaging the piston body 20 so as to integrate therewith. The microneedle member 30 has a base 31 and a plurality of microneedles projecting from a surface of the base 31.