Abstract: A lancet is pressed against a puncture needle cartridge while fitting a puncture needle loading inlet of the lancet to the axis of a puncture needle on the puncture needle cartridge. At this time, in order to facilitate the operation, one of plural puncture needles arranged in parallel is tilted up from its initial position at a predetermined angle, and the puncture needle is guided into a puncture needle holding rod of the lancet, and simultaneously, the puncture needle is pressed up to a position where the rear end part of the needle pushes the bottom surface of a puncture needle loading chamber of the puncture needle holding rod, whereby the puncture needle is loaded. When discarding a used puncture needle, the puncture needle is inserted into a lancet guide member of the puncture needle cartridge, whereby the puncture needle is reliably captured to be discarded.

Abstract: A lancet comprises a slider having a puncture needle holding mechanism at its one end; a cam ring which has a continuous cam groove, is rotatable about a support shaft, and has a cam ring claw and an anti-return claw for restricting the rotation; a ring spring for applying a force to rotate the cam ring; a rotatable stopper arm for holding and releasing the rotation of the cam ring; and a rotatable ratchet for restricting the direction of rotation of the cam ring. A puncture needle unit comprises a puncture needle body which is integrally molded with a protrusion to be fitted to the lancet, a rotation stop rib, and a puncture needle; and a puncture needle cap which is lightly pressed into the puncture needle body.