PURPOSE: To make a long-distance driving method achievable even in case of a small bore pipe being low in rigidity.

CONSTITUTION: A pilot body 1 to be driven into the ground via an earth-moving screw conveyor 3 is installed by a propeller 4 set up in a starting shaft 5, and a connecting member is installed in the rear of this pilot body 1 free of slide motion in the longitudinal direction and a propulsive force transmitting means which connects a small bore pipe to be embedded in this connecting member and also connects an interval between the pilot body 1 and the connecting member till tensile load action on the small bore pipe 2 is reached to the allowable tensile load, and allows that this interval between the pilot body 1 and the connecting member is slid as far as the specified distance at a time when the tensile load is reached to the allowable tensile load. In addition, an auxiliary propulsive means which presses a rear end of the small bore pipe 2 to the propeller 4 is installed there as well, and thus long-distance propulsion in the small bore pipe 2 being low in rigidity is made achievable.