Characteristics　of　the　large　self-weight　and　large　load　of　heavy　machine　tool,　lead　to　the　change　of　ground　motion　character,　its　dynamic　response　is　directly　affected　by　pile-soil　structure.　This　paper,　through　the　introduction　of　large　guide　joint,　the　pile　soil　contact　surface,　boundary　conditions　of　artificial　interception　area　and　the　equivalent　stiffness　and　damping,　builds　an　easily　achieved　soil-pile-heavy　machine　tool　dynamic　model,　studies　the　system　step　response　law　in　the　different　soil　layer,　provides　the　theory　basis　for　the　foundation　soil　design　of　heavy　machine　tool..