The sandwich-type complex Na(H2O)6(C6H16O3N)2[Na2(H2O)7(C6H16O3N)]2[(Na(H2O)2)3- (Cu(H2O))3(BiW9O33)2]・14H2O (1) (C6H16O3N+ = protonated triethanolamine) has been synthesized and structurally characterized by single-crystal X-ray diffraction, IR spectroscopy and TG analysis. The basic framework of 1 is built from a sandwich-type [(Na(H2O)2)3- (Cu(H2O))3(BiW9O33)2]9− anion, two [Na2(H2O)7(C6H16O3N)]3+ cations, a free Na(H2O)6+ cation, and two free C6H16O3N+ units. In compound 1, the [(Na(H2O)2)3(Cu(H2O))3- (BiW9O33)2]9− anion links two bi-nuclear units [Na2(H2O)7(C6H16O3N)]3+ to form a [Na2- (H2O)7(C6H16O3N)]2[(Na(H2O)2)3(Cu(H2O))3(BiW9O33)2]3− cluster, and a new 3D supramolecular structure is further constructed by hydrogen bonding interactions among this cluster, the free Na(H2O)6+ cation, and the free C6H16O3N+ cations. Crystal data: Cu3Na8Bi2W18C24H150O121N4, monoclinic, C2/c, a = 14.5668(13), b = 23.0405(13), c = 37.412(2) Å , β = 91.569(10)° , Z = 4.