The　design　of　cushion　is　the　key　to　the　design　of　a　composite　foundation.　Through　the　finite　element　analysis,　the　relationship　of　the　settlements　of　the　pile　and　soil　with　the　load　is　found.　And　the　influence　laws　of　the　cushion　thickness　and　its　compression　modulus　on　the　stress　ratio　of　pile-soil　and　the　settlements　of　pile　and　soil　are　obtained.　The　research　results　will　provide　a　theoretical　evidence　for　the　suitable　selection　of　the　cushion　thickness　and　its　materials　and　will　be　beneficial　to　the　optimum　design　of　composite　foundations.