Abstract We investigate the electronic and transport properties of a MoS 2 monolayer transducer with some simple gas molecules, such as CO, CO 2 and NO to explore theoretically sensing capabilities of this monolayer. The calculations are performed using nonequilibrium Green's function (NEGF) formalism based on the density functional theory (DFT) as implemented in the TranSIESTA code. Exposure to the NO gas molecule influences dramatically the electron transmission and the current–voltage characteristics of the MoS 2 monolayer. The results predict that the MoS 2 monolayer transducer can monitor the NO gas molecule to 10 4 order among these molecules between ±0.9 V bias window using the current–voltage characteristic with high sensitivity and selectivity. Here, post-processed analyses predict that the sensing mechanism is based on the charge transfer, which it in turn causes remarkable electrostatic gating to occur for the NO adsorbate. The numerical results may be useful to engineer and design gas sensor based on the MoS 2 monolayer.