Underground fishing tool

The utility model discloses an underground fishing tool, and belongs to the technical field of oil and gas development. Comprising a fishing spear, a drill rod joint and an outer barrel, and a plurality of outer fishing hooks are arranged on the fishing spear; the upper end of the outer barrel body is fixed on the drill rod joint, is coaxially arranged outside the fishing spear and extends downwards relative to the fishing spear, a plurality of inner fishing hooks are arranged on the inner wall of the outer barrel body, the distance between the inner wall of the outer barrel body and the outer fishing hook is larger than twice of the diameter of a steel wire, milling teeth are arranged at the bottom of the outer barrel body, and a liquid drainage hole is formed in the outer barrel body; the inner fishing hook is located below the fishing spear, the lower end of the inner fishing hook is fixed to the inner wall of the outer barrel and is obliquely inwards arranged from bottom to top, and the upper end of the i