The　pyrolysis　characteristic　of　phenolic　foam　was　investigated　by　use　of　thermogravimetry-Fourier　transform　infrared　spectrometry-mass　spectrometry(TG-FTIR-MS).　The　results　show　that　pyrolysis　process　can　be　divided　into　three　stages.　At　the　first　stage,　the　mass　loss　rate　is　low,　and　the　gases　of　small　molecular　mass,　such　as　H2O　and　HCHO,　escaped　physically.　The　second　stage　is　the　beginning　of　pyrolysis　reaction,　at　which　H2O,　HCHO,　CO2,　SO2,　SCH4(methanethiol)　and　C2NH5(aziridine)are　produced.　At　the　third　stage,　the　main　chain　fractures　and　pyrolyses,　CO2　is　spawned.　Generation　rate　of　C2NH7(　dimethylamine),　CH2O2(formic　acid),　HCHO　and　C2NH5　reach　maximum.　At　425.58°C　the　mass　loss　rate　attain　maximum,　-1.4787%/min.　The　pyrolysis　reaction　of　phenolic　foam　in　this　stage　is　the　most　violent.　The　sum　of　mass　loss　at　the　second　and　third　stage　is　84%　of　the　whole　mass.　The　whole　process　of　mass　loss　ends　at　565.20°C.