A gas sensor based on microelectromechanical systems (MEMS) technology containing a sensitive layer was designed, simulated, and fabricated. The gas sensor consists of a silicon substrate, a platinum microheater, gold interdigitated electrodes, and a sensitive layer. The active area with dimensions of is located at the center of a sensor (). The experimental results show that the microheater provided heating for the sensitive layer at low power consumption and accurate temperature control. At a power consumption of only 40 mW, the temperature reached 319°C at the center of the MEMS platform with uniform heating. In addition to that, the above mentioned gas sensor exhibited a high response to with optimized sensitivity recorded at the working temperature of 170°C. With 10 ppb of , the response of the sensor could reach up to 5.8 and the power consumption is 17.2 mW.