Thin film gas sensors made of nanocomposite MWCNT center dot SnO2(1:66), semiconductor compound WO3 center dot SnO2(1:9), and also multicomponent structure MWCNT center dot SnO2(1:66)/WO3 center dot SnO2(1:9) have been fabricated by high-frequency magnetron sputtering and electron-beam deposition methods. Sensitivity of the prepared sensors to influence of gases, such as hydrogen, methane, butane, and also ethanol vapors, was investigated. Sensors made of MWCNT center dot SnO2(1:66) and WO3 center dot SnO2(1:9) show appreciable sensitivity to hydrogen and alcohol vapors already at working body temperature 100-150A degrees C. Sensors made of MWCNT center dot SnO2(1:66)center dot WO3 center dot SnO2(1:9) can be used for detection of low concentrations of hydrogen and ethanol vapors; besides, monotonous increase in the structure sensitivity with increase in content of the alcohol vapors allows one to apply these sensors also for fast detection of concentration of these vapors in air.