A lab-scale free fall reactor was employed for fast pyrolysis of pine wood chip at a temperature range from 550 to 750 degrees C with a sweep gas flow rate of 20 or 500 mL/min. With increasing the pyrolysis temperature from 550 to 750 degrees C, the gas yields were significantly enhanced, but the liquid yields were reduced. The highest gas yield, 67.3 wt%, was obtained after pyrolysis at 750 degrees C with a sweep gas flow rate of 20 mL/min, while the highest liquid yield, 46.8 wt%, was obtained at 550 degrees C with a sweep gas flow rate of 500 mL/min. Unexpectedly, char yields increased with increasing sweep gas flow rate. The gas products and liquid products after fast pyrolysis were analyzed by gas chromatography and gas chromatograph-mass spectrometry, respectively.