The nano γ-Fe2O3/ZnO double-layer film gas sensor was fabricated by the screen printing technology and the hydrothermal method. XRD and SEM techniques were used to characterize the phases and morphologies of the film. The gas sensing properties of the gas sensor to ethanol were investigated. The result shows that the gas sensitivity of the gas sensor is higher than that of the nano γ-Fe2O3 single-layer film gas sensor and the nano ZnO single-layer film gas sensor. The high gas sensitivity of the nano γ-Fe2O3/ZnO double-layer film to ethanol was caused by the combined effect and nano effect.