Abstract: A graphene/phenolic(GNS/PF) resin composite was prepared by blending a graphene oxide suspension with an emulsion of phenolic resin in water, followed by reduction with hydrazine and curing at 160℃. AFM, SEM, FT-IR and TG-DTG were performed to reveal the effects of graphene on the morphology, structure, thermal stability and char yield of the composites. Results showed that GNS was uniformly dispersed in the PF matrix. Strong adsorption of GNS on the PF resulted in an ordered arrangement of PF along the GNS plane. The density of crosslinks in the PF matrix was drastically increased after curing and its thermal stability and char yield were remarkably improved. The thermal decomposition peak temperature was increased from 382.7℃ for pure PF to 408℃ for the GNS/PF composites and the char yield of pure PF at 900℃ was increased from 46.2% to 59.4% for that in the composite containing 0.65 wt% graphene oxide.