An interspinous gap fixator comprises a fixator body provided with a positioning circular groove with one side provided with a bullet-shaped bit and the opposite side provided with a stopping board. The bit is provided with at least one spiral groove extending from the front edge of the bit to the positioning circular groove. In addition, the outer side of the stopping board is provided with a pivotal structure which can be assembled with a rotary handle to engage the fixator between two adjacent spinous processes. With the positioning circular groove of receiving the upper and lower spinous processes for fixation, so as to achieve the purpose of stabilizing interspinous gap.
