The　coastal　region　of　Fujian　contains　numerous　existing　stone　masonry　structures,　many　of　which　are　constructed　on　soft　soil　sites.　Previous　studies　have　shown　that　the　soil-structure　interaction　(SSI)　effect　on　soft　soil　foundations　can　prolong　the　structure＇s　natural　vibration　period　and　enhance　its　seismic　response.　We　develops　a　soil-structure　interaction　system　model　and　a　comparative　rigid　foundation　model　using　the　finite　element　software　LS-DYNA　to　investigate　the　impact　of　SSI　on　the　dynamic　characteristics　and　seismic　response　of　stone　structures.　The　results　indicate　that　the　SSI　effect　alters　stone　structures＇　dynamic　properties　and　seismic　response.　This　alteration　is　evident　in　the　extended　natural　vibration　period,　which　reduces　overall　stiffness,　increases　interstory　displacement　angles,　and　slightly　decreases　the　acceleration　response.　Under　both　SSI　and　FIX　systems,　the　structural　failure　mode　is　characterized　by　the　external　collapse　of　the　second-story　stone　walls,　which　causes　the　roof　stone　slabs　to　lose　support　and　fall,　leading　to　overall　collapse.　The　FIX　system　demonstrates　better　structural　integrity　and　stability　with　slower　crack　development.　In　contrast,　the　SSI　system　exhibits　cracks　that　appear　earlier　and　develop　more　rapidly,　causing　more　severe　damage.　The　research　findings　provide　a　theoretical　basis　for　the　seismic　reinforcement　of　existing　stone　structures　on　soft　soil　foundations.　©　2025　China　Earthquake　Networks　Center.