In the structure of the title compound, {[Na(C6H15N3O3)]Br} n , the sodium cation and the bromide anion are both located on threefold rotation axes. The sodium cation is bonded to the three hy-droxy groups of one 1,3,5-triamino-1,3,5-tride-oxy-cis-inositol (taci) ligand, with the taci ligand residing around the same threefold rotation axis as the sodium ion. The coordination sphere of the sodium ion is completed by three amino groups of three neighbouring taci mol-ecules. Hence, this type of coordination constitutes a three-dimensional open framework with channels along the c axis which are filled with the bromide counter-anions. Each bromide ion forms three symmetry-related hydrogen bonds to both the hy-droxy and the amino groups of neighbouring taci ligands.