Subgrade　vibration　characteristics　during　concrete　pavement　rehabilitation　with　impact　roller　were　studied　by　three　dimensional　elastic-plastic　dynamic　FEM,　and　the　calculation　results　were　verified　by　feild　test　data.　Based　on　the　results　of　field　monitoring　data,　the　dynamic　time　history　responses　of　different　buidings　under　subgrade　vibration　and　construction　safety　distance　were　analyzed.　The　results　indicated　that　subgrade　vibration　induced　by　impact　rolling　load　has　impact　transient　property,　the　vertical　vibration　acceleration　is　that　maximum　between　vertical,　longitudinal　and　transverse　vibration　acceleration,　the　vibration　accelerations　decaies　significantly　in　the　range　of　10　m　away　from　the　impact　source;　and　vibration　acceleration　increases　a　little　with　impact　times;　increase.　Subgrade　vibration　has　little　dynamic　effect　on　buildings　15　m　far　away　from　the　impact　source;　and　buildings　resonance　effet　is　little　it　is　advised　that　the　safety　distance　is　15m　far　away　from　the　impact　source　for　the　buildng　in　good　condition,　and　20m　for　human.