Abstract: A bone marrow biopsy needle provided with blades which cut and retain a biopsy core. In one embodiment, the cutting blades of the needle are hinged at the distal end of the needle and are mechanically coupled to an actuator at the proximal end of the needle. The needle is preferably formed with inner and outer walls to provide a space therebetween for the mechanical coupling. The cutting blades are retained in a dead space against the outer wall of the needle when the needle is open. In lieu of a hinged arrangement, the outer wall of the needle may be tapered at its distal end so that the blades are forced together when they are pushed forward. In another embodiment, the cutting blades are pre-curved inward, but are retained against the inner surface of the needle wall until pushed forward. In yet another embodiment, the distal ends of the cutting blades rest within a curved circumferential recess provided in the needle wall, and, when pushed forward, move together to cut and retain the biopsy core.