Abstract: By use of the method of integral equation,the second kind Fredholm’s integral equation was deduced to solve the interaction factors of pile-pile,pile-soil and soil-soil.Using the principle of superposition,the piled raft foundation was calculated.The validity of the proposed method was verified through comparison with solutions obtained using other methods by existing theories of elasticity.Finally,a series of parametric analysis was made to study the settlement of piled raft foundation and the loads shared by the individual pile and subsoil.The proposed method could be readily used to analyze the large piled raft foundation.