With　the　rapid　development　of　bridge　engineering　in　China,　multi-span　cable-stayed　bridges　have　become　one　of　the　main　structures　of　modern　highways　and　railways　for　crossing　rivers　or　straits.　In　this　study,　a　1:100　scale　model　of　a　three-tower　cable-stayed　bridge　was　tested　using　a　shaking　table　array　system.　The　mechanism　associated　with　the　seismic　response　of　the　scale　model　under　uniform　and　non-uniform　excitations　was　clarified.　The　results　from　the　tests　indicated　that:　(1)　the　strong　vibration　responses　of　the　main　girder　and　towers　under　four　different　horizontal　earthquake　wave　excitations　were　identified,　and　the　seismic　responses　of　the　scale　model　were　most　evident　under　uniform　Jiangxin　(JX)　wave　excitation;　(2)　the　seismic　performances　of　the　main　girder　and　towers　of　the　scale　model　were　adversely　affected　by　traveling　wave　effects,　especially　when　the　wave　velocity　exceeded　616　m/s,　which　suggests　that　traveling　wave　effects　should　be　considered　in　the　seismic　design　of　multi-tower　cable-stayed　bridges;　(3)　when　the　peak　acceleration　value　of　the　El　Centro　(EC)　wave　reached　4.0　m/s(2),　shear　failure　of　the　bearing　of　the　middle　tower　first　appeared.　This　kind　of　shaking　table　tests　will　help　to　improve　our　understanding　of　dynamic　performance,　and　will　be　especially　useful　in　the　design　process　and　numerical　simulation　of　multi-span　cable-stayed　bridges　with　large　span　subjected　to　spatially　varying　earthquake　ground　motions.