In order to provide the relevant basis for the industrial production of co-fermentation of cellulosic ethanol distiller's grains and dung, this experiment used cellulosic ethanol distiller's grains and cow dung as raw materials,adopted the self-made anaerobic fermentation device, and compared mechanical stirring（MS） and mechanical reflux mixed stirring（MRMS） fermentation process. The results show that: compared with the mechanical stirring fermentation process, the gas production rate, material utilization rate and total nitrogen removal rate using by MRMS were increased 41.2%, 13% and 9.1%, respectively, and the chemical oxygen demand removal rate was reduced 10.3%.