To provide a drill tool capable of exhibiting a function of a vibration exciter to the maximum by efficiently discharging concrete powder produced by drilling.

In a drill tool 1 generating vibration force which acts in the axial direction of a bit drive shaft 3 and its magnitude pulses, by rotating eccentric weights 15, 16 by a motor in reverse direction to each other, and generating vibration moment which acts in the rotation direction of the bit drive shaft 3 and its magnitude pulses, a ventilation path 3a is provided inside the bit drive shaft 3, and is formed to supply compressed air to the ventilation path 3a. The compressed air supplied to the ventilation path 3a is blown out from the tip end of the diamond bit 4.