Abstract: The invention discloses a single cone earth boring bit which is adapted to be used for boring in oil fields, mining and geological prospecting. The single cone earth boring bit is composed of a bit body (1), gauge blocks (2), active cutting gauge teeth (4), passive gauge teeth (3) and knobby cone (6) etc. On the knobby cone (6), there are inserted wear-resistant teeth intermittently or successively, so as to make the wear resistance of the bit cutting system to be matched with the service life of the bearing. At the same time, gauge blocks (2) are provided on the bit body which may be directly made on or welded to the bit body. On the gauge blocks (2), there are inserted common carbide or wear-resistant active cutting gauge teeth (4) and the passive gauge teeth (3) to enhance the gauge-protecting effect of the bit. Such a single cone earth boring bit can significantly increase the footage of the bit and reduce the cost for drilling.