There is considerable demand for identification of non noble metal based catalysts and catalyst supports for water electrolysis. Theoretical approaches provide an ideal framework for identifying such systems. In an attempt to identify new electrochemically stable catalyst supports for electrolysis of water, the electronic structures of MgNb2O6, MgTa2O6, ZnNb2O6, and ZnTa2O6 compounds doped with elements from 3A, 3B, 5B, 6A groups of the Periodic table as well as F from group VII have been calculated using the Vienna ab-initio simulation package (VASP), within the projector augmented-wave (PAW) method in the general gradient approximation (GGA) for conducting the exchange-correlation corrections. The role of incorporating the additional elements in improving the electronic conductivity as well as the structural and chemical stability is discussed. Based on the calculated values of the cohesive energies for the materials and their type of electronic conductivity, we hypothesize that introduction of group 3A elements (Sc and Y) as well as F contribute drastically to the improvement of the electronic properties including the chemical stability of all four Mg and Zn tantalates/niobates based parent oxides. Results indicate that these doped compounds might serve as candidate catalyst supports proton exchange membrane (PEM) based water electrolysis. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.007210jes] All rights reserved.