Hard rock film coating dill bit

The invention discloses a hard rock film coating dill bit. The hard rock film coating dill bit comprises two bit tools and a drill bit body, the bit tools are symmetrically arranged on the drill bit body, and the bit tools are wear-resisting reinforced bit tools. Body protecting alloys distributed peripherally are located at the positions, located at the lower ends of the bit tools, of the drill bit body, water through holes are formed in the drill bit body, drill bit retreating blades are symmetrically arranged at the positions, located at the lower ends of the bit tools, of the drill bit body, and the drill bit retreating blades are installed on the drill bit body through rotating shafts. Connecting rods which are movably installed are arranged on the drill bit body, the connecting rodsare of a round structure and water through holes are arranged in the center positions of the connecting rods, a fixing block used for preventing the mutual rotation of the connecting rods and the drill bit body is arranged at