A 2D coordination polymer built by sodium ion and water-soluble p-sulfonatothiacalix[4]arene of trivalent yttrium complex [Na(H2O)(2)Y(H2O)(6)(DMF) (p-sulfonatothiacalix[4]arene)]center dot 9H(2)O is reported. The complex belongs to the monoclinic system, space group P2(1)/c. with a 16.703(3), b = 17.819(4), c = 17.357(4) angstrom, beta = 106.23(3)degrees, Z = 4, V = 4960.0(17) angstrom(3), M-r = 1304.08, D-c = 1.746 g/cm(3), mu = 1.624 mm(-1), F(000) = 2688, the final R = 0.0398 and wR = 0.1132 for 7534 observed reflections with I > 2 sigma(I). One yttrium(III) ion is coordinated by the thiacalixarene ligand via the sulfonato group, and also ligated by an oxygen atom of a DMF molecule occupying the cavity of thiacalixarene and six aqua ligands.