We report for the first time on the gas sensing properties of novel ball milled and nitrided Mg-TiO2 prepared powder. Ball milling was performed on an Mg-TiO2 powder mixture for 60 hours (h), yielding a reduction in crystallite sizes. The milled powder was annealed in nitrogen at 650 degrees C, and crystalized into two face centred cubic (FCC) phases with different lattice parameters. The nitrided powder sample exhibited various morphologies including nanorods, as well as nanoparticles showing porous behaviour. The AFM and BET analyses showed high roughness and surface area for 60 h milled Mg-TiO2 nanostructures. The Mg-TiO2 60 h and Mg-TiO2-60 h-N-2 materials were tested for their sensing performance towards H-2, NH3 and CH4 gases at various temperatures. The Mg-TiO2 60h sensing material showed high sensing response to NH3, disclosing fast response-recovery time and high selectivity to NH3. (C) 2015 Elsevier B.V. All rights reserved.