The (1E, 2E)-(4-bromophenyl)(hydroxyimino)acetaldehyde oxime complexes, [ML2], M = Co(II), Cu(II), and Ni(II), were synthesized and characterized by elemental analysis, magnetic susceptibility, FT-IR spectra, and thermal analysis techniques. The optical band gap of this ligand and its complexes were determined by UV-vis spectrophotometer in the wavelength range 300–800 nm. A decrease in the energy band gap of the [CoL2], [NiL2], and [CuL2] complexes has been observed compared with LH ligand. Temperature-dependent conductivity measurements showed that all samples behave like semiconductor. Activation energies calculated from Arrhenius plots showed that the conduction occurs via both intramolecular and the intermolecular processes.