A serious concern affecting the life and environment around us is the air pollution. Release of noxious disturbing gases and particulate matter around us has largely put our lives on hold. These toxic and pernicious gases are an outcome of various sources like industries, vehicles or automobiles, waste and stubble burning, etc. The use of metal oxide-based gas sensors serves as right and an appropriate choice in monitoring and detecting hazardous gases like CO, NOx, H2S, SO2, NH3, etc. which puts a detrimental impact on us. The current chapter focusses on the study of tungsten oxides which are an example of metal oxides that can be used as gas sensors owing to their large sensitivity, quick and fast responsiveness, and recyclability with long duration stability. The transition metal oxide, i.e., tungsten oxide (WO3), has widely been utilized in various gas sensing applications. This review will help in comparing various works done by researchers in gas sensing applications using tungsten oxide.