In this paper we present a gas multi-sensor composed by an optimized low consumption (55mW-500°C) and low cost (microelectronics process) micro-hotplate and by three different metal oxides (CuO, ZnO and SnO2) sensing materials deposited by inkjet directly on the membrane. The realized structures have shown a stable and reproducible behavior. By using a specific temperature-modulated profile associated to a multivariate classifier, we have realized an electronic nose able to detect selectively four gases (alone and mixed) at low concentrations (CO-100ppm, NO2-0.2ppm, NH3-5ppm and C2H4O-2ppm).