To make it possible to integrally form a needle tube and a needle hub by reliably holding and fixing the needle tube with a chuck member and then performing insert molding.A device has a needle tube (5) having a needle tip (5A) capable of puncturing a living body and a needle hub (6) that is adapted to hold the needle tube (5) in a state where the needle tip (5A) of the needle tube (5) is protruded and that is formed with a retention hole (26) into which a chuck member is inserted, the chuck member being adapted to hold and fix the circumferential surface of the needle tube (5) when performing insert molding.
