Bad geological conditions are often encountered in bored pile construction process, which cause local collapse of hole wall and soil mixing into concrete in the concrete grouting; these lead to bored pile broken, concrete defects in pile body and insufficient bearing capacity of pile end. High pressure circulation grouting with steel pipe underpinning reinforcement technology can be very good to deal with the problem. Take high pressure circulation grouting with steel pipe underpinning reinforcement technology as the research object and with the engineering case of pile foundation reinforcement, analysis is made on the design, calculation and application; the reinforcement effect is tested by core-collection, test results show that the bearing capacity of pile foundation meets the design requirements after reinforcement.