In the title complex, [Ni(C(12)H(9)N(2)O(3)S)(2)(H(2)O)(2)]·4H(2)O, the Ni(II) ion is coordinated by four N atoms from two bidentate chelating 4-[(pyridin-2-yl)methyl-idene-amino]-benzene-sulfonate ligands and two O atoms from cis-related water mol-ecules in a slightly distorted octa-hedral environment [Ni-N = 2.071 (3)-2.121 (3) Å and Ni-O = 2.071 (2) and 2.073 (3) Å]. In the crystal, the coordinated water mol-ecules and the four water mol-ecules of solvation are involved in inter-molecular O-H⋯O hydrogen-bonding inter-actions with water and sulfon-ate O-atom acceptors, giving a three-dimensional framework structure.