Three　compounds　of　tungstosilicic　acid　and　tungstosilicic　salt:　K3H[SiW12VI　O-40]　.　3H(2)O(I),　(H3O)(4)　[H3SiW9VI　W-3(V)　O-40]　.　2H(2)O(II)　and　[(CH3)(4)N](4)　[(SiW12O40)-O-VI]　.　4.5H(2)O(III),　with　Keggin　structure,　have　been　synthesized.　The　relationship　between　their　properties　and　structures　was　studied　by　using　FTIR,　NIR　FT-Raman,　UV-Vis　and　flurescence　etc.　They　possess　isolated　[SiW12O40]　cage　anion,　which　combines　with　cation　and　water　by　static　electric　action　and　weak　hydrogen　bond;　The　study　of　their　FTIR　and　Raman　spectra　shows　that　the　vibrational　frequencies　of　the　group　are　related　to　the　structure　of　the　materials.　For　the　compound　II,　the　vibrational　frequency　of　nu(as)(W=O-d)　decreases　as　part　of　W6+　are　reduced　to　W5+,　and　the　charges　of　anion　group　affect　nu(as)(W-O-c-W),　nu(as)(Si-O-a)　and　delta(O-a-Si-O-a)　etc.　apparently.　In　UV-Vis　spectra　of　compound　I　and　II,　there　are　two　characteristic　peaks　at　200　and　260　nm,　respectively.　The　fluorescence　spectra　of　compound　I　were　studied,　and　showed　that　the　emission　peak　is　at　350,　440,　520　and　675　nm　excited　by　220,　350　and　440　nm.