The new oxalato-bridged dinickel(II) complexes of hexaaza macrocyclic ligands 1-3, which incorporate functional groups such as -OH. -CN and -CH₃ into the pendant arms attached at the uncoordinated bridgehead nitrogen atoms, are prepared by the reactions of Ni(II) complexes of ligands 1-3 with oxalate anion. The complexes are in a octahedral geometry in solution, and here, the NI(II) ion coordinated by four secondary nitrogen atoms of the macrocycle and two oxygen atoms of oxalate anion. The pendant hydroxyl and nitrile groups in [Ni₂(L)₂OX]²⁺ (L : 1-2) do not coordinate Ni(II) ion in solution. The spectroscopic properties of these complexes are not affected significantly by the nature of the pendant functional groups.