The, ligand bis (2-amino-1,3,4-thiadiazole) (L) has been synthesized by the reaction of oxalic acid with thiosemicarbazide. The ligand and Ni (II) complexes have been synthesized and its structures of these compounds have been deter mined by elemental analysis, spectrometric magnetic susceptibility and molar conductivity measurements. Coordination numbers of monomeric Ni (II) complex are six and four, respectively. From the elemental analysis and mass spectral data, the complexes were proposed to have the formula [Ni(L)2(SO4)H2O].0.5DMF. 2H2O. Ni (II) complexes are paramagnetic and non-electrolytes.