The paper establishes the regularities of the oxidation of combustible substances in the presence of catalytic systems of different nature and on their basis the catalysts for measuring and compensation sensitive elements of a thermocatalytic ethanol vapor sensor are selected. The possibility of creating highly sensitive and selective sensors with the use of measuring and compensating thermosensitive elements of the sensor containing catalysts of different activity to the components of complex gas-air mixtures has been experimentally confirmed.The main metrological characteristics and operational parameters of the developed selective thermocatalytic ethanol sensors are estimated. The developed utensils allow the determination of ethyl alcohol vapors in wide ranges of its concentrations and have the best metrological characteristics and operational parameters.