The invention relates to the technical field of oil and gas exploitation well drilling and in particular relates to a tubular column structure enhancing coiled tubing drilling well horizontal extending capacity. The upper end of a measurement while drilling assembly of the device is connected with a bit pressure automatic control pup joint; the bit pressure automatic control pup joint communicateswith the measurement while drilling assembly and can automatically control bit pressure; the upper end of the bit pressure automatic control pup joint is connected with an underwell rotation powder device; the underwell rotation power device can produce a rotary torque driving a lower part tubular column to rotary drill; and the underwell rotation power device can receive a control instruction ofthe measurement while drilling assembly when orientation of the underwell rotation power device is required, and the torque output can be stopped. By the use of the tubular column structure, a high-rigid tubular column part of the coiled tubing drilling wellcan possess composite drilling capacity and self-traction driving capacity; a drill bit can be precisely controlled to acquire stable bit pressure; coiled tubing spiral bend effect can be reduced, horizontal section rock debris settlement can be lowered; damping and friction can be decreased; and horizontal extending capacity of the coiledtubing drilling well can be greatly improved.