The electronic and adsorption properties of three different alcohol molecules namely methanol, ethanol and 1-propanol vapors on MoS2 nanosheet is investigated using DFT method. The structural stability of MoS2 nanosheet is ascertained with formation energy. The adsorption properties of alcohol molecules on MoS2 base material is discussed in terms of average energy gap variation, Mulliken charge transfer, energy band gap and adsorption energy. The prominent adsorption sites of methanol, ethanol and 1-propanol vapors on MoS2 nanosheet are studied in atomistic level. The projected density of states (PDOS) spectrum gives the clear insights on the electronic properties of MoS2 nanosheet. The PDOS and energy band structure confirmed the adsorption of alcohol vapors on MoS2 nanosheet. The variation in the band structure and PDOS is noticed upon adsorption of methanol, ethanol and 1-propanol molecules on MoS2 nanosheet. The PDOS spectrum also reveals the variation in peak maxima owing to transfer of electron between alcohol molecules and MoS2 base material. The adsorption of 1-propanol vapor on MoS2 nanosheet is observed to be more favorable than other alcohol molecules. The findings confirm that monolayer MoS2 nanosheet can be used to detect the presence of alcohol vapors in the environment. (C) 2017 Elsevier B.V. All rights reserved.