Abstract　Carbon　foams　were　prepared　by　direct　pyrolysis　of　cyanate　ester　(CE)　resins　from　the　mixtures　of　phenol　novolac　cyanate　ester　(PNCE)　and　bisphenol　A　cyanate　ester　(BACE)　at　ambient　pressure.　Pyrolysis　behaviors　of　the　CE　resins　were　characterized　by　thermogravimetric　analysis　(TGA),　scanning　electron　microscopy　(SEM)　and　X-ray　diffraction　(XRD).　In　addition,　influences　of　PNCE/BACE　mass　ratio　on　the　characteristics　of　the　resultant　carbon　foams　were　studied.　Results　show　that　the　CE　resin　possesses　better　thermal　stability　with　increasing　PNCE/BACE　mass　ratio,　whereas　its　self-foaming　performance　becomes　worse　during　pyrolysis.　The　addition　of　PNCE　to　BACE　leads　to　an　increase　in　the　bulk　density　of　the　resultant　carbon　foam　but　a　decrease　in　both　its　porosity　and　open　cell.　Moreover,　the　compressive　strength　of　the　carbon　foam　increases　with　an　increase　in　the　PNCE/BACE.　When　the　PNCE/BACE　mass　ratio　varies　from　0　to　0.75,　the　compressive　strength　of　the　carbon　foam　prepared　increases　from　3.25　to　9.6　MPa.　©　2015　Elsevier　B.V.