Rigid pile composite foundation is more and more widely used, and it is worth studying the problem that how to reasonably determine the bearing capacity of rigid pile composite foundation and calculating settlement, especially in some special geological conditions. There exist some problems in calculating the bearing capacity of rigid pile composite foundation by the current standard method, such as the problems that bearing capacity of hard soil foundation is larger than that of composite foundation after the depth and width modification, and the bearing capacity of soil between piles of layered foundation is also unclear. To solve the problem, the p~s curve of composite foundation can be obtained based on the principle of deformation coordination between pile and soil. According to the p~s curve of composite foundation, it is easy to determine the bearing capacity of composite foundation based on strength safety and deformation control. This method can better solve the problem in determining bearing capacity of composite foundation. It has been proved by case analysis in this paper for reference.