Abstract: The gas product evolved from animal manure pyrolysis was studied at a heating rate of 30℃/min by thermogravimetric analysis coupled with fourier transform infrared spectroscopy (FTIR). Experimental results showed that the gas products mainly evolved at the temperature range of 250-500℃, and the main gas products were H2O, CO, CO2 and CH4 etc.. The evolution curves of H2O showed a peak at about 150℃ and another peak at about 350℃. The CO2 evolution curves took on a much higher peak at about 350℃ and a small peak at about 710℃. The CO evolution curves took on a peak at about 350℃ and a higher peak at about 710℃, and there was only one peak at about 530℃ in evolution curves of CH4. The results can provide a reference for design and optimization of pyrolysis reactor.