Substitution of cation in metal oxides could give different properties with potential in some applications. Li2xMg(1-x)O was prepared by substitution of magnesium with lithium in magnesium oxide to form new materials which were Li0.2Mg0.9O and Li0.4Mg0.8O. They were synthesized using a sol-gel method. The samples were characterized using X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The band gap energies of the samples were obtained from measurements using a UV-vis Spectrophotometer. The crystalite size of the MgO samples was sub-micron while that of the Li substituted samples were larger. It was found that there were quite drastic differences in the band energies of MgO and Li2xMg(1-x)O materials. (C) 2012 Published by Elsevier B.V.