The　Multicomponent　heteropoly　compounds　[Me4N](3+x)[PVxMoyW12-x-yO40].n(H2O)　with　Keggin　structure　have　been　synthesized,　and　have　been　characterized　by　FTIR　and　NIR　FT-Raman.　The　vibrational　regularity　of　oxygen-containing　bonds　(P-O-a,　M　=　O-d,　M-O-b-M　and　M-O-c-M)　in　these　heteropoly　compounds　have　been　studied.　The　vibrational　frequencies　v(as)　(M　=　O-d)　and　v(as)　(M-O-b-M)　was　shown　to　prove　the　reason　why　the　acidity　of　the　heteropoly　compounds　descended　and　the　oxidation　increased　by　the　substitution　of　V　atoms.