The pyrolysis and combustion characteristics of polyurethane(UA, UB, Foam) have been studied to investigate the effective treatment way by using TGA, GC-MS, FT-IR. To obtain the information on the kinetic parameters of thermal decomposition of polyurethane, the dynamic thermogravimetric analysis curve and its derivative have been analyzed by Friedman methods. Product's properties of pyrolysis of polyurethane were studied at various heating rates, and then combustion experiments were performed as changes of temperatures and oxygen concentration, were investigated what is produced and created formation process of toxic gases and their quantity. From the kinetic analysis, even if values make a little difference as additives kinds, the apparent activation energies of polyurethane in N2 atmosphere are 165∼195 kJ/mol and TGA analysis showed one-step reaction under N2 but two-reaction was appeared under air. Pyrolytic oil was composed of alcohol and polyol on the whole but not so good in yields and the composition of products were not changed for various heating rates. In combustion, toxic gases(hydrogen cyanide, acetonitrile etc) break out high molecular weight aromatic compounds created by recombination and replacement reactions as increase of temperature and oxygen concentration.