Abstract: Pyrolysis characteristics and kinetics of wheat straw were investigated using a thermogravimetric analyzer coupled with Fourier transform infrared analyzer (TG-FTIR) under catalytic and noncatalytic conditions. The effects of pyrolysis temperature and catalyst on composition of volatile products were discussed. The pyrolysis parameters were obtained based on TG and DTG curves. The composition of pyrolysis products was online analyzed by FT-IR. The results show that two thermogravimetric peaks appear on DTG curves using nickel oxide and calcium oxide as catalyst, but only one peak appears without the catalysts. Thus the biomass pyrolysis characteristics can be improved under catalytic condition. Nickel oxide has more remarkable effect on increasing biomass pyrolysis yields, picking up volatile releasing rate, and decreasing apparent activation energy. CO and CO2 release peak is consistent with the maximal weight loss rate in DTG. CH4 is formed later than CO and CO2. In addition, using nickel oxide and calcium oxide as catalyst CO and CH4 yields increase, whereas CO2 yield decreases. While temperature is below 800℃, calcium oxide is more helpful to improve fuel gas composition during pyrolysis. When the temperature is above 800℃, nickel oxide has better catalytic effect.