To remarkably reduce cost and labor required for manufacturing a device by simplifying a structure of a guide member, by easily fixing a boring tool to the guide member arranged along a surface of an object to be bored.

The guide member 2 arranged along the surface of the object T to be bored, has a contour bar 3 and a guide pin 4 erected in the vertical direction to the surface of the object T. The boring tool 10 is provided with a drill adapter 20 fitted to this guide pin 4. The drill adapter 20 has a fitting groove for fitting the guide pin 4 and a fixing means for locking the guide pin 4 in the fitting groove. The guide pin 4 of the guide member 2 is fitted to the fitting groove of the drill adapter 20 by moving the boring tool 10 toward the object T along a predetermined boring shaft. The guide pin 4 is also fixed inside the fitting groove by operating the fixing means by moving the boring tool 10 toward the object T.