The present disclosure relates to an apparatus for curing spinal stenosis which is an abnormal narrowing of the spinal canal between spinous processes, more particularly, to an apparatus of fixing spinous processes which can prevent the narrowing or widening of the spinal canal between spinous processes along the motion of the spine so as to enhance spinal stabilization. The apparatus of fixing the spinous processes includes a spacer having at least predetermined portion inserted between spinous processes of two neighboring vertebrae to support the spinous processes so as to prevent narrowing of the spinous processes which is generated by spinal bending; and a clip provided to cover an outer surface of the spinous processes of the two neighboring vertebrae to prevent widening of a distance between the spinous processes generated by the spinal bending.