A　(3,12)-connected　3D　inorganic　luminescent　lanthanide　hydroxide　cluster　polymer　[Eu(6)(mu(6)-O)　(mu(3)-OH)(8)(H(2)O)(6)(SO(4))(4)](n)　(1)　has　been　hydrothermally　synthesized　and　characterized.　The　structure　can　be　considered　to　be　constructed　by　linking　12-connected　octahedral　hexanuclear　lanthanide　oxido/hydroxide　clusters　with　3-connected　inorganic　SO4(2-)　anions.　Presently,　it　is　the　first　3D　inorganic　lanthanide　cluster　polymer　based　on　octahedral　hexanuclear　lanthanide　cluster　with　the　highest　connected　binodal　network　topology.　1　displays　red　luminescent　emission　and　exhibits　the　characteristic　transitions　of　the　Eu(3+)　ion　with　a　decay　lifetime　of　196.25　mu　s　in　the　solid　state　at　room　temperature.