The present invention relates to a spacer device for fixing a band between spinous processes, the spacer device comprising: a band unit which has a certain degree of tension and is disposed between a spinous process and an adjacent spinous process which protrude from the vertebrae, on the outer circumference of the spinous process and on the outer circumference of the adjacent spinous process so as to mutually fix the spinous process and the adjacent spinous process and a spacer unit which is coupled to the band unit and is disposed in a space between the spinous process and the adjacent spinous process so as to fix the end of the band unit, wherein the spacer unit moves along the band unit from the outside of the body to the inside of the body in a state where the band unit penetrates the spacer unit, and thus the spacer unit is inserted into the space between the spinous process and the adjacent spinous process. Thereby, the spacer device can: efficiently and reliably fix the end of a band for mutually fixing adjacent spinous processes, while permitting fine motion during surgery for treatment of spinal diseases acquire optimal procedure results and efficiently carry out surgical procedures regardless of skill due to a relatively inexpensive and simple configuration take action in accordance with the body types of various patients and provide a patient with a state identical to that of original vertebrae since a firmly fixed state can be maintained and, simultaneously, fine motion is permitted following a procedure.