Hydrogen monitoring in industrial premises, when other gases are also present in the air, is an urgent task. For safety reasons, it is necessary that a hydrogen sensor provides measurements at the lowest possible temperature. In this paper, we propose an approach to the selective measurement of the concentration of hydrogen, which is a part of multicomponent hydrocarbon mixtures. Binary and ternary mixtures of hydrogen with methane, propane, and butane were used in this study. The traditional method is based on measuring the catalytic sensor response, and a new method that is based on measuring the amount of heat released during hydrogen combustion was used to solve the problem of selectivity. An industrial catalytic sensor was used for the measurements. It was shown that for the selective measurement of hydrogen in hydrocarbon mixtures, it is necessary to reduce the sensor temperature below 200 ℃. Measurements of hydrogen concentration and comparison of results were carried out at 105 ℃. Such low operating temperature is an excellent result for a catalytic sensor. It is shown that the method based on measuring the amount of heat released during hydrogen combustion is more accurate than the traditional method, and the average error was 7.7%.