Abstract: A microsensor system, in particular gas sensor system, is integrated on a single chip and includes a microsensor, preferably a resistive-film-sensor configuration, with a microheater, the latter preferably of essentially round, elliptic or polygonal structure. The microsensor is located on a thermally insulated semiconductor structure, e.g. a thin membrane. Further included or integrated on the chip may be one or more first circuits for controlling the microheater and/or second circuits for evaluating or processing the measured values obtained from the microsensor. The first circuits may include power and/or temperature controller for the microheater. The second circuits may include an A/D converter, a digital signal processor, a digital output interface for processing sensor signals and transferring them to external devices, and/or potentiostats to regulate the electrode potential applied to the gas-sensitive layer.