In this work, molybdenum disulfide (MoS2)-modified graphene (MoS2/GNS) hybrids were prepared by the hydrothermal method and characterized by X-ray diffraction (XRD), Laser Raman spectroscopy (LRS) and transmission electron microscope (TEM). The characterization results show layered molybdenum disulfide was deposited on the surface of graphene nanosheets (GNSs) and grahene oxide was reduced simultaneously. Thermogravimetric analysis results of MoS2, GNS and MoS2/GNS hybrids showed that incorporation of MoS2 increased the thermal oxidation resistance of the graphene evidently. Compared to pure epoxy resins (EP), the addition of MoS2/GNS hybrids into EP enhanced the onset thermal degradation temperature (T) with an 53 degrees C increment under air atmosphere and an 18 degrees C increment under nitrogen atmosphere. The addition of MoS2/GNS hybrids endows excellent flame retardant properties to EP, confirmed by the dramatically reduced peak heat release rate value and total heat release value. Moreover, the addition of MoS2/GNS hybrids dramatically decreased the smoke products.