According to the actual situation of extremely complex hydrogeological conditions of Fengfeng mining area, individual water inrush and frequent mining process hazards are serious, the grouting treatment technology was taken. Problems in thin limestone 5.5 m thick aquifer region advanced grouting reinforcement were analyzed, drivepipe to Daqing limestone aquifer top, whipstock cutting drivepipe, pinnate branch hole grouting were adopted to achieve thin limestone aquifer region grouting reinforcement, which provided reference for 5.5 m thin limestone aquifer region grouting reinforcement.