Analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was applied to achieve fast pyrolysis of poplar wood and on-line analysis of the pyrolysis vapors. Experiments were conducted to reveal the distribution of pyrolytic products under different pyrolysis temperatures (300-1000 degrees C) and times (5-30 s). During the fast pyrolysis process, the poplar wood started decomposition to form organic volatile products at the set temperature of 300 degrees C, and reached the maximum volatile product yield at around 550 degrees C. The products included various anhydrosugars, furans, phenolic compounds, linear carbonyls, linear acids, hydrocarbons, and so on. They exhibited different formation characteristics. Based on the experimental results, we discussed the possible pyrolytic pathways for the generation of the major products. (C) 2011 Elsevier Ltd. All rights reserved.