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 having a needle tip capable of puncturing a living body and a needle hub that is adapted to hold the needle tube in a state where the needle tip of the needle tube is protruded and that is formed with a retention hole into which a chuck member is inserted, the chuck member being adapted to hold and fix the circumferential surface of the needle tube when performing insert molding.