There are bottom sediment and slurry skin at pile side in bored piles, so that the bearing capa- bility of piles can not fully develop. Post-grouting technique can eliminate the above inherent defect and enhance the bearing capability. The adaptability of post一grouting and the increasing range of the bearing capability are different in different bearing strata. The increasing range of the bearing capability is sum- marized according to the numerous examples of construction projects in Beijing, Shanghai, Tianjin and Wuhan. After comparing and analyzing these data and considering the safe reserve, the general increasing range of the bearing capability has been put forward in the above four regions. The advised general increas- ing range can provide reference to design and construct bored pile after grouting.