This paper summarizes four kinds of pile-rock interface models that are frequently used in FEM simulation for rock-socketed pile. An improved hyperbolic model of load-transfer for rock-socketed pile is proposed to resolve the problem of parameter selection based on the most common and effective hyperbolic model of load-transfer according to the elastic solution of thick-wall cylinder and the theoretical research about the shear strength of the discontinuities ordered roughness without filler (Patton(1966)). The “Load Transfer -FEM” named united model is put forward according to FRIC subroutine which applies the improved hyperbolic model of load-transfer on the strength of the ABAQUS (CAE). The bearing behavior and load transfer mechanism for rock-socketed pile reflected by the results from applying united model to analyze static loading test agree well with field measurements.