The crystal structure of the title complex, [H3NCH2CH2NH3] [Ni(H2O)6] [SO4]2, has been determined by single-crystal X-ray diffraction methods at 295 K, being refined by full matrix least squares to a residual of 0.032 for 2532 independent 'observed' reflections. Crystals are monoclinic, P21/n, a 13.148(3), b 7.119(3), c 8.245(2) Ŭ ߠ100.97(4)ꬠZ = 2. Both cations are disposed about crystallographic centres of symmetry. The organic species has a necessarily planar non-hydrogen atom skeleton [C-C, 1.513(3); C-N, 1.485(4) ŝ. In the hexaaquanickel(11) species, the Ni-O distances are very similar [2.060(2), 2.064(2), 2.066(2) ŝ, although there is a significant departure from octahedral symmetry among the angles [89.71(8), 86.87(8), 90.00(8)Ꝯ The oxygen atoms of the water molecules are bonded pseudo-tetrahedrally. The centrosymmetric metal atom environment is more regular than that in the corresponding Tutton salts, to which complexes of the present type may present an attractive alternative.