The electronic transport properties and trimethylamine adsorption (TMA) characteristics on MoO3 molecular device are explored using density functional theory (DFT) method via GGA/PBE exchange correlation functional. The density of states spectrum visualizes the localization of charges in MoO3 molecular device upon adsorption of TMA. The transport properties of MoO3 molecular device with adsorption of TMA are studied in terms of transmission spectrum. I-V characteristics of MoO3 molecular device reveal the change in the current upon adsorption of TMA. The present work gives an understanding on MoO3 molecular device, which can be used as an efficient TMA sensor. (C) 2015 Elsevier B.V. All rights reserved.