The invention discloses a ground drill corrector and an operation method thereof, particularly provides a ground drill corrector which is simple in structure, convenient to operate and capable of improving the working reliability of a ground drill, and an operation method of the ground drill corrector. The ground drill corrector comprises a pair of gantries, a support plate, a jack and a positioning mechanism, wherein the pair of gantries takes the shape of a hollow square; each gantry comprises a top plate, a bottom plate and a pair of side plates; the pair of gantries is connected onto the support plate in a sliding manner; a through hole is formed in the middle of the support plate; the jack is arranged inside the through hole of the support plate; the jack is positioned right below the ground drill; a hoop and a sliding hole are arranged on the bottom side of each top plate of the pair of gantries; the hoops are used for fixing one end of the ground drill; the sliding holes are used for containing the other end of the ground drill; the positioning mechanism comprises a hydraulic rod I, a hydraulic rod II, a laser range finder I and a laser range finder II; the hydraulic rod I, the laser range finder I and the hoops are positioned on the same side; the hydraulic rod II, the laser range finder II and the sliding holes are positioned on the same side. By adopting the ground drill corrector, the labor can be saved in construction, the correction reliability is improved, and adjustment can be facilitated.