The present invention provides an inexpensive surgical guide preparation tool by which an insertion hole for implant can be correctly and easily formed at a predetermined position.The surgical guide preparation tool has a pair of marker members opposing to each other and a gauge body which has a support member for connecting the marker members, and the gauge body is attached to a surgical guide body. The surface of each marker member is provided with grid-like lines which are recognisable by a CT scanned image and disposed longitudinally and laterally at substantially regular intervals predetermined marks are chosen from intersections of the grid-like lines, and a guide ring is attached to the surgical guide body so that a direction connecting the chosen marks is used as an axial direction of the guide ring. The axial direction of the guide ring is used as an insertion direction for implant.
