A positioning insert for two adjacent vertebral bodies includes a plate like insert adapted to fix relative positions of the two adjacent vertebral bodies and provided with a sharp edge oppositely formed relative to the dull side and first holes defined through a side face of the plate like insert, wherein the sharp edge is formed to have an angle between 5 to 15 degrees; and an annular insert adapted to be inserted into a space between the two adjacent vertebral bodies and having second holes and a slot defined in a peripheral side face thereof to accommodate the plate like insert so as to have the plate like insert received in the slot.