Abstract: According to the in-site static uplift tests and stress measurement results of five cast-in-situ piles with large diameter, the load transfer behavior of rock-socketed uplift piles and the characteristics of the lateral friction in pile-rock interface are analyzed. The uplift coefficients of soil strata and the method to determine the ultimate bearing capacity of Q–s curves are obtained. It is shown that the shape of curves is related to the rock weathering of bearing strata and rock-socketed depth. The effect of pile-rock interface on the lateral friction is discussed with its development process.