Roller cone drill bit efficiency time during drilling depends, to a large extent, on the properties of the materials from which the components of the roller cone bit are made. The faster the roller cone bit is worn, due to the effects of the rock material through which we drill and the drilling regimes used during the drilling, the worse is the efficiency of drilling and the higher is the number of drill bits needed to drill the well. The aim of our research was to determine the mechanisms of wear on roller cone bit materials according to the characteristics of the steel material of the roller cone bit and the characteristics of the rock material, in this case, sandstone on the drilling regime. The results of the discovered wear mechanisms help us to anticipate the possible improvement of the resistance of the unprotected roller cone bit steel material to excessive wear and, consequently, the longevity of the roller cone bit. For this purpose, we examined the steel materials of the roller cone bit, which we used during well drilling and the rock material, sandstone, through which we drilled with the roller cone bit under consideration. The results of our analysis present the mechanisms that result in the wear of the roller cone bit material under the given conditions of the rock material and the drilling regime. The results of the discovered wear mechanism can be used to improve the material of the roller cone bits in order to achieve a longer operating life and decrease the related costs of drilling.