Abstract: Through the problem which clay layer anchor rod drilling tool the hole appears by the past is analysised, the immediate cause of the blocking holes and the collapsed hole that the old style core drilling tool and the short screw drilling tool became in the hole proce in the horizontal direetion small angle, the soil loss of the original balance of the stress caused by drilling reduetion diameter, so that soil disturbance can not be timely output hole. Thus the long screw anchor holed drilling tool is developed, the question that holed harassed the earth output has solved, the innovation rotary vane has solved the problem of the drill hole endophragrn earth granular structure relaxation. The phenomenon that anchor rod holed has stopped up in the clay layer is settled thoroughly. The angle which anchor rod holed designs is guaranteed. A set of the comparatively standard rules that long screw anchor holed drilling tool operating forms.