The title Ni-II complex, [Ni(C7H4ClO2)(2)(C6H6N2O)(2)(H2O)(2)], is centrosymmetric with the Ni atom located on an inversion centre. The molecule contains two 2-chlorobenzoate (CB) and two nicotinamide (NA) ligands and two water molecules, all ligands being monodentate. The four O atoms in the equatorial plane around the Ni atom form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination is completed by the two N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxyl group and the adjacent benzene ring is 29.48 (16)degrees, while the pyridine and benzene rings are oriented at a dihedral angle of 83.16 (5)degrees. In the crystal structure, O-H center dot center dot center dot O and N-H center dot center dot center dot O hydrogen bonds link the molecules into infinite chains. pi-pi Contacts between the benzene and pyridine rings [centroid-centroid distance = 3.952 (1) angstrom] may further stabilize the crystal structure. There is also a C-H center dot center dot center dot pi interaction.