The instrument for morcellating, in particular for endosurgical operations, includes a tube with a cutter formed at its distal end which is the actual morcellator, and a gripping instrument introduced into this tube for holding the tissue to be removed. Between the gripping instrument and the cutting tube is provided a protective sheath into which the gripper of the gripping instrument is inserted before the beginning of the cutting procedure. This configuration reliably prevents fouling between the cutting instrument and the gripper.