Pre-reinforced pile in high cutting slope can reduce the displacement of the slope and ensure the stabilization of the slope. Because of the largely structural stiffness of concrete pre-reinforced pile, the earth pressure acting on pile increases. In order to settle this problem, a layer of EPS backs on to the pre-reinforced pile was set to decrease the interaction force of pre-reinforced piles. Finite element analysis software of ANSYS was used to analyze the value and distribution of displacement, shearing force and bending moment acted on the pre-embedded pile with different thickness and types of EPS backs on to the pre-reinforced pile. The results showed that the thickness and types of EPS have large influence on pre-reinforced piles. With the increase of the thickness of EPS, the earth pressure acting on pile decreases, the displacement of pre-reinforced pile decreases, and the inner force of pre-reinforced pile decreases. With the decrease of the density of EPS, the earth pressure acting on pile decreases, the displacement of pre-reinforced pile decreases, and the inner force of pre-reinforced pile decreases.