In　the　paper　earthquake　simulation　shaking　table　test　of　masonry　buildings　(MBs)　with　or　without　RC　framed　lower　floor　(LF)　and　associated　nonlinear　dynamic　response　analysis　are　described.　In　the　analysis　the　skeleton　curve　characterizing　the　interstory　restoring　force-displacement　relationship　of　MB　consisting　of　four　linear　segments　was　used,　and　the　values　of　the　relevant　characteristic　points　on　the　curve　were　suggested.　The　good　agreement　of　the　analytical　results　with　the　experimental　results　shows　that　the　proposed　skeleton　curve　and　the　values　of　the　relevant　parameters　are　appropriate.　To　achieve　a　better　understanding　of　the　seismic　performance　of　three　kinds　of　MBs,　including　MB　with　one　LF,　MB　with　two　LFs　and　MB　without　LF,　a　great　number　of　nonlinear　dynamic　response　analyses　were　conducted.　In　the　analyses　16　earthquake　ground　accelerations　recorded　from　different　soil　site　conditions　were　used　as　the　input　motions.　Numerical　results　show　that　the　seismic　performance　of　MB　with　LF(s)　greatly　relates　with　the　site　conditions.　For　I-III　site　classes　the　MB　with　LF(s)　exhibits　higher　seismic　resistance　than　the　whole　MB　(i.e.　MB　without　LF),　and　the　MB　with　two　LFs　exhibits　higher　seismic　resistance　than　that　with　one　LF.　For　IV　site　class　three　kinds　MBs　considered　have　comparable　seismic　resistance.　Besides,　from　the　dynamic　response　analysis　a　rational　story　stiffness　ratio　of　lowest　masonry　floor　and　its　adjacent　LF　of　within　2.5　and　the　maximum　permissible　total　height　of　21m,　or　the　maximum　permissible　story　number　of　seven　are　suggested　for　region　of　seismic　intensity　of　VII.