The reduced graphene oxide/α-Fe2O3 (rGO/α-Fe2O3) hybrid nanocomposites have been prepared by a facile hydrothermal approach. The components and morphologies of the as-synthesized products were analyzed by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). NO2 sensing properties of rGO/α-Fe2O3 nanocomposites are tested at room temperature (25°C) with NO2 concentration ranging from 0.1 to 5.0ppm. It is demonstrated that the rGO/α-Fe2O3 nanocomposites based sensor exhibited enhanced response (3.86) for 5ppm NO2 compared to pure rGO (1.38). The improved sensing features can be attributed to this hybrid sensor of synergistic effect between the highly conductive graphene and the α-Fe2O3 nanoparticles.