Cr2O3 doped ZnO thick films have been prepared by screen printing technique and firing process. These films were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), and EDX. H2S gas sensing properties of these films were investigated at different operating temperatures and different H2S concentrations. The 7 wt. % Cr2O3 doped ZnO thick films exhibits excellent H2S gas sensing properties with maximum sensitivity of 99.12 % at 300 oC in air atmosphere with fast response and recovery time.