Gas-sensitive properties of γ-Fe2O3 thin film, deposited on Si-substrate of new design, have been studied in this work. The layers were formed by using sol-gel derived γ-Fe2O3xnH2O colloidal solution. Structural features of the films and peculiarities of iron state were obtained by employing XRD, HR-TEM, IR and Mössbauer spectroscopy. High sensitivity of the mentioned sensor to CH4 has been established.