To provide a ground drill machine which can drill a hole having a long length (large depth) and a relatively large diameter, in the ground.

The ground drill machine carries out drilling of the hole H by emitting laser light 1 and dissolving the ground G. The ground drill machine is formed of a sealing means M for sealing the interior of the drilled hole H, a laser light emitting means R for emitting laser light 1 to a bottom surface B of the drilled hole H sealed by the sealing means M, a pipe P inserted into the sealed hole H, for ejecting materials dissolved by the laser light 1 to the outside, and a pressurizing means K for pressurizing the interior of the sealed hole H.