In each of the two mol-ecules in the asymmetric unit of the title compound, [Ni(C(13)H(18)NO(4)S)(2)(C(5)H(5)N)(2)(H(2)O)], the geometry of the Ni(2+) ion is an extremely distorted trans-NiN(2)O(4) octa-hedron, arising from its coordination by one water mol-ecule, two pyridine mol-ecules, and one O-monodentate and one O,O'-bidentate deprotonated N-p-tolysulfonyl-l-leucine ligand. In the crystal, mol-ecules are linked by N-H⋯O and O-H⋯O hydrogen bonds, forming chains along the c axis. An intra-molecular O-H⋯O hydrogen bond occurs in one of the mol-ecules.