The invention discloses a large-dip-angle inclined well raise boring reaming drill bit falling prevention mechanism which comprises a falling prevention bolt and falling prevention nuts. Threads are arranged on the outer wall of the upper end of the falling prevention bolt, and a falling prevention component is fixedly connected with the tip of the lower end of the falling prevention bolt; a flared opening with a downward large opening end is formed in a middle hole in a joint of a central pipe and a drill bit, and cylindrical through holes are formed in middle holes in the upper side and thelower side of the flared opening; the upper end of the falling prevention bolt sequentially penetrates a middle hole of the central pipe and a central hole of a connector drill rod and is connected with the falling prevention nuts above the connector drill rod in a threaded manner, the outer diameters of the falling prevention nuts are larger than the hole diameter of the central hole, the fallingprevention component is positioned at the flared opening, and the outer diameter of the lower portion of the falling prevention component is larger than the hole diameter of a small opening end of the flared opening. The large-dip-angle inclined well raise boring reaming drill bit falling prevention mechanism has the advantages that drill rods and reaming drill bits which are positioned below broken portions can be prevented from falling after the drill rods are broken, drill tools can be prevented from being secondarily destructed by huge impact momentum when the reaming drill bits fall intoraise boring lower opening roadways, and the construction safety further can be improved.