Flexible gas sensor fabricated by direct laser patterning and its gas sensing properties towards ozone and ammonia are reported. The flexible platform consists in Ti/Pt interdigited electrodes for gas detection and a microheater device. The platform validation has been realized by thermal simulation and its electrical properties have been also studied. The gas sensing properties were investigated using a commercial ink of ZnO nanoparticles at several concentrations and temperatures. The sensor presents excellent responses toward ammonia and ozone at 300 °C and 200 C° respectively, with good reproducibility, and fast response and recovery time in a wide range of concentrations.