Abstract: Firstly,the development of the generalized composite foundation theory was expounded based on a review of the development of composite foundation techniques.Through the comparison among the load transfer mechanisms of shallow foundation,pile foundation and composite foundation,it was pointed out that the essence of the composite foundation was that both piles and soils beared the loading together directly,and the relationship among the above three foundation types was discussed.Then the forming condition of composite foundation and the importance of forming condition were studied.The relationship of composite foundation and ground treatment,composite foundation and double-layered foundation,composite foundation and composite pile foundation were studied.The influence of the foundation rigidity and the bedding cushion on the behavior of composite foundation,the characteristics of the displacement field of composite foundation under loading,the principle of the optimum design of the composite foundation and the design of composite foundation according to settlement were discussed.Type of composite foundation,practical methods to calculate the bearing capacity and settlement of composite foundation were introduced.A case study of the application of the generalized composite foundation theory to highway engineering was discussed.Finally,some proposals concerning further development of the generalized composite foundation theory and its application were put forward.