The pyrolysis of polybutadiene (PB) under an inert atmosphere at different temperatures is investigated by using differential thermal analysis (DTA) and pyrolysis-gas chromatography (Py-GC). Fourier transform-infrared spectroscopy (FT-IR) is used for investigating the resulting residue. The pyrolyzed gaseous products are analysed by gas chromatography (GC). The effect of temperature on the relative yields of the major decomposition products is studied. Based on these data, the thermal degradation mechanism of PB is proposed.