Abstract: It is common to consider internal forces and deformation of piles under lateral loads. However, the lateral soil movement due to adjacent excavation can also generate additional internal forces and deformation in pile foundation of adjacent buildings, and it may lead to damage of adjacent pile foundation. Based on assumed soil movement and the Winkler’s foundation model, a variational solution is developed. According to the principle of the minimum potential energy, the variational control equation is established to solve this problem under different pile head restraints. The validity of the proposed method is demonstrated through comparison with the existing theoretical solutions and experimental results. The simplicity of using the proposed solution makes it a good alternative approach to analyze the behavior of piles subjected to lateral soil movement.