The utility model provides a long screw drilling bored pile post-grouting technology device constituted by a reinforcing cage, a pile side grouting tubes, a pile bottom grouting tube, and a grouting valve. The grout can be injected into the soil body through the grouting pipe and grouting valve, when the reinforcing cage is vibrated and inserted in place and meets the grouting requirement. The device solves the application problem of the post-grouting technology in the long screw drilling bored pile, and enables the safe and correct installation of the grouting pipe according to the design requirement without being damaged during the vibrating and inserting process of the reinforcing cage. In the utility model, requirement of grouting technology is promoted, whereby the post-grouting on the grouting pipe fastened on the reinforcing cage is conducted, so that the soil body on the pile side and pile end is solidified and strengthened, the piling quality and the carrying capacity of individual pile are greatly improved, especially in the layer of sand, the circular-gravel layer, and the pebble layer, and the engineering costs can be reduced.