the invention relates to a drilling tool comprising a support shank and an interchangeable cutting insert which is fitted to the support shank and which has an asymmetrical main lip divided into a guide lip having a supporting land and a guide land trailing the supporting land , and into a clearance lip having a trailing clearance portion , wherein a guide land and a supporting land are formed on the lateral surface of the support shank and continuously extend the guide land and the supporting land , respectively , on the cutting insert and additionally guide the drilling tool on the inner wall of a drill hole during a drilling operation .