By　incorporating　graphene　oxide　(GO)　into　phenolic　resin　(PR),　GO/PR　composites　were　prepared,　and　the　effects　of　the　content　and　reduction　degree　of　GO　on　thermal　resistance　of　GO/PR　composites　were　studied.　The　peak　degradation　temperature　of　the　PR　was　increased　by　about　14　degrees　C　with　GO　which　was　heat　treated.　The　char　yield　of　GO/PR　composite　at　a　GO　weight　fraction　of　0.5%　was　about　11%　greater　than　that　of　PR.　The　interactions　such　as　covalent　bonds　and　pi-pi　stacking　between　GO　and　PR　were　regarded　as　the　main　reason　for　the　enhancement.　Located　at　the　GO-PR　interface,　GO　effectively　anchored　and　structured　PR　molecular　near　the　surfaces　of　GO　sheets,　and　thus　facilitated　the　formation　of　char.　The　superiority　of　GO/PR　composites　over　PR　in　terms　of　thermal　properties　enhancement　should　also　be　related　to　the　promoting　graphitization　by　the　addition　of　GO.　(C)　2013　Elsevier　Ltd.　All　rights　reserved.