Provided is a drilling device for acromioplasty including an outer tube assembly including including a head section having a rotor having a first power transmission unit having a hollow structure and configured to receive power and a twist drill coupled to a lower end of the rotor with a hollow structure and provided with a suction port formed on an outer circumferential surface thereof, and an outer tube having a tubular shape and having one end to which the head section is coupled, an inner tube assembly including an inner tube having a hollow structure and rotatably inserted into the outer tube assembly, a second power transmission unit having a hollow structure and formed at one end of the inner tube to transmit power to the first power transmission unit, a rotation transmission unit formed at the other end of the inner tube and configured to receive a rotational force from the outside, and a discharge section disposed between the rotation transmission unit and the inner tube to discharge ground bone wastes to the outside, and a connecting pipe configured to connect the twist drill and the inner tube such that the ground bone wastes is discharged to the outside.
