Pyrolysis and direct combustion processes were applied to pomace obtained from olive oil production in Bayer/ICI/Shell (BIS) and Verbant der Chemische Industrie (VCI) furnaces. The volatile and semi-volatile products derived from both processes taking place in each furnace were captured on XAD resins at selected temperature and non-volatiles were obtained after extraction of the resins with acetone. The qualitative and quantitative determinations were carried out by using a gas chromatograph coupled with mass spectrometry. It was found that the compound distribution at different temperatures in the combustion process were wider than for the pyrolysis in the BIS furnace. The compounds obtained at lower temperatures during pyrolysis and combustion in the VCI furnace showed similarities, although a larger number of compounds were obtained at 800°C in the combustion process than in the pyrolysis process.