Downhole drilling tool separation tool for shale gas extended reach well drilling

The invention relates to the technical field of shale gas well drilling, in particular to a downhole drilling tool separation tool for shale gas extended reach drilling. The lower end of a second stage top joint of the downhole drilling tool separation tool is provided with a plurality of elastic claws, and the multiple elastic claws are distracted by a limit sleeve and are embedded and fixed in alimiting groove of the inner wall of a second stage lower joint; and the limit sleeve is fixed to the inner wall of the second stage lower joint through a second stage shear pin, a ball seat matchedwith a second stage steel ball is arranged at the upper end of the limit sleeve, and interlocking teeth of the second stage lower joint is connected with the interlocking teeth of the second stage topjoint in a matched mode. According to the downhole drilling tool separation tool for the shale gas extended reach drilling, two stages of separation mechanisms are possessed, an upper drilling tool of a clamping point can be poured rapidly from the clamping point, and the reliability is high; no midway disengagement in the drilling process occurs, the drilling risk is reduced, and the torque of the upper drilling tool can be transmitted to apply to a lower drill bit during drilling; and tools are simple in use and easy to operate, and the time for handling accidents is shortened, thereby increasing drilling efficiency and saving drilling cost.