PURPOSE: To excavate horizontally a channel by rotating a bucket formed by providing a cutter and an earth introduction opening on the side of the cylindrical body and a bottom lid that opens and closes freely and has a cutter and an earth introduction opening on the underside of the cylindrical body.

CONSTITUTION: An earth drilling bucket 17 is pivoted swingably to the tip of the arm of a hydraulic shovel. The earth drilling bucket 17 is comprised of a rotation driving device 19 and a rotating bucket rotated with the rotation driving device 19. The rotating bucket is made up of a cylindrical body 20, an earth introduction section 54 provided on the side of the body, a cutter 50 on the side of the body near the earth introduction section 54, a guide 59 that guides earth introduced into the body to the center, and a bottom lid 34 that opens and closes with regard to the opening of the underside of the bucket body 20 and has a cutter 37 and an earth introduction section 36, thereby excavating a channel while moving the bucket horizontally.