Abstract: Karst is a very common adverse geological phenomenon in China. Due to its distribution and characteristics of complexity and uncertainty, the difficulty of foundation design and construction of high-rise buildings in karst areas is increased significantly. A high-rise building in Tangshan karst area has the type of pile raft foundation. The test results of test piles do not meet the design requirements. Through analysis of the causes and summarization of experience, the test results completely meet the design requirements after the adjustment of the design and construction of pile foundations. The rock-socketed depth should be based on the code and test piles combined with the construction survey data. The construction survey is very necessary, and it is the important basis for determining the design of pile length reasonably. The grouting construction technology for the pile side and pile end is adopted, which can eliminate the karst hazards, and it can effectively improve the bearing capacity of pile foundation, which is the organic combination of karst treatment and foundation construction.