To provide a drilling pipe which can preferably perform operations of the supplying of a cleaning agent and the picking of ground water when penetrating the pipe into ground, supplying the cleaning agent to contaminated soil and picking ground water, and is inexpensive.

The drilling pipe can pick ground water and supply a cleaning agent to contaminated soil via through-holes 7 bored on side surface of the drilling pipe 1 while being penetrated into the ground. Each of the through-holes 7 is bored by irradiating a laser beam along parts to become a circumference thereof. An irradiation angle for the drilling pipe 1 of a laser beam is differentiated in accordance with a part on the circumference of the through-hole 7. When viewing the through-hole 7 bored by the laser beam with a line of sight facing the whole inner circumferential surface from the inside of the drilling pipe 1, an opening of the through-hole 7 on the inner circumferential surface side of the drilling pipe 1 is surrounded by the opening of the through-hole 7 on the outer circumferential surface side of the drilling pipe 1.