ABSTRACT: In the title compound, [Ni(C(20)H(22)N(2)O(4))]·H(2)O, the Ni(II) ion and the water mol-ecule are located on a twofold rotation axis. The Ni ion is coordinated by two N [Ni-N = 1.8462 (18) Å] and two O [Ni-O = 1.8645 (14) Å] atoms in a distorted square-planar geometry. The water mol-ecule and the Ni complex mol-ecule are paired via O-H⋯O hydrogen bonds.