Considering　the　interaction　between　visco-elastic　layered　soils　and　integral　pile,　the　dynamic　response　at　the　pile　head　to　an　arbitrary　dynamic　load　is　theoretically　investigated.　By　Laplace　transforms　and　the　transmit　property　of　impedance　function,　the　analytical　expression　of　the　impedance　function　and　displacement　and　velocity　response　function　at　the　pile　head　in　frequency　domain　and　in　time　domain　are　derived.　The　characteristic　of　interaction　between　soil　layers　and　pile　is　theoretically　investigated.　The　results　indicate　that　dynamic　characteristics　of　upper　layer　soil　are　major　factors　that　affect　the　complex　stiffness　of　pile.　Pile　stiffness　increases　and　damping　decreases　with　increasing　modulus　of　upper　soil.　Because　of　the　change　of　soil　modulus,　admittance　curves　of　pile　have　cycle　characteristics　which　have　big　peak　and　small　peak.　When　the　modulus　of　upper　soil　is　higher　than　that　of　lower　layer　soil,　the　reflection　wave　shape　in　time　domain　at　soil　division　surface　and　initial　pulses　are　on　the　contrary.　Conversely,　they　are　the　same.　In　genaral,　reflection　wave　shape　in　time　domain　at　soil　division　surface　is　flat　and　the　amplitude　is　not　very　large.