In the title complex, [Ni(C(9)H(4)N(2)O(4))(C(12)H(8)N(2))(H(2)O)(2)](n), the Ni(II) atom is hexa-coordinated by one N and one O atom from two different 1H-benzimidazole-5,6-dicarboxyl-ate ligands, two N atoms from one 1,10-phenanthroline ligand and two water mol-ecules. The flexible 1H-benzimidazole-5,6-dicarboxyl-ate ligands link the Ni(II) centres, forming an infinite zigzag chain parallel to [001]. The crystal packing is governed by inter-molecular hydrogen-bonding inter-actions of the O-H⋯O, N-H⋯O and C-H⋯O types.