This　paper　discusses　the　difference　between　the　strong　ground　motion　of　reclaimed　soil　sites　and　those　of　free-field　ground　motion.　We　determine　under　what　conditions　the　influence　of　reclaimed　soil　can　be　ignored,　and　the　ground　motion　on　the　reclaimed　soil　site　can　be　regarded　as　a　free　field.　Finite　element　models　of　reclaimed　soil　were　constructed　by　analyzing　the　actual　situation　of　strong　ground　motion　observation　on　reclaim　soil　sites.　Using　a　＇lumped　mass　explicit　dynamic　finite　element＇　method,　the　effects　of　shear　wave　velocity　and　thickness　of　reclaimed　soil　on　free-field　ground　motion　are　analyzed.　Replacing　thicker　reclaimed　soil　with　remolded　soil　is　proposed　to　reduce　the　impact　of　reclaimed　soil　sites　on　the　ground　motion　of　free　field　sites,　the　effects　of　which　are　analyzed　by　numerical　simulation.　Results　show　that　the　ground　motion　peak　and　the　response　spectra　of　the　reclaimed　soil　site　are　significantly　different　from　those　of　the　free　field　site.　With　increasing　reclaimed　soil　thickness,　the　influence　is　more　noticeable.　The　impact　of　reclaimed　soil　on　the　free-field　site　can　be　reduced　with　reclaimed　soil　being　replaced　by　remolding　soil.　The　conclusions　provide　a　theoretical　basis　for　the　rational　use　of　strong　ground　motion　records　on　the　reclaimed　soil　site　and　the　construction　of　strong　motion　stations.　©　Published　under　licence　by　IOP　Publishing　Ltd.