Abstract To study the influence of a foundation structure on the ground, the finite layer method of composite ground is derived based on the finite layer method (FLM) theory of the semi-analytic numerical method and the force method principle of elastic material, which is used to analyze a layered ground including multiple internal constraint planes. By simplifying a pile body as a solid constraint composed of four side plane constraints, the composite ground FLM is applied to solve the displacement and stress field of the ground. The change of the ground displacement and stress caused by the addition of a single pile constraint are then discussed, and the influence rules of a pile position on the ground displacement are also determined. Finally, the necessity, rationality and validity of the composite ground FLM are demonstrated by the model test examples of a single pile and pile raft foundation.