Abstract: Disclosed is a reamer for implant surgery including: cutting front end portions each of which has a sharp front end; cut edges of a horizontal line form, the cutting front end portions and the cut edges being arranged radially and alternately, wherein one side of the cutting front end portion having the sharp front end has a triangular depressed face inclined downwardly toward a rotation central axis of the cutting part, and one side of the cut edge having the horizontal line form has a triangular inclined face inclined downwardly toward the outer circumferential surface of the cutting part, wherein an inclination angle of a side inclined edge inclined downwardly at the sides of the outer circumferences of the cutting front end portion and the cut edge becomes gradually smaller in the rotation direction of the cutting part.