Abstract: Sequencing Batch Reactor(SBR) system was tested in the laboratory for treating animal wastewater pretreated with septic tank. Through studying the relationship between the treatment effects and the aeration time, operating mode, load of active sludge, ratio of filled water and ambient temperature, the optimal operating conditions for SBR process were determined and applied to the pilot animal wastewater treatment system on a dairy farm. The results showed that the removal efficiencies of pollutants can be more than 90% when the ambient temperature is over 15℃, and the effluent can also satisfy the local discharge standards with post-treatment if the temperature is too low.