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The disposal of swine wastewater poses a considerable challenge for both farmers and the environment. Simultaneous biological nitrogen and phosphorus removals from solids separated swine wastewater with high organic matter were investigated in a lab-scale anaerobic-anoxicanaerobic- anoxic/aerobic sequencing batch reactor ((AO)2SBR). The SBR was operated with three cycles per day, temperature at 20oC, sludge retention time (SRT) at around 22 days and hydraulic retention time (HRT) at three days. Under the periodical circulation with different oxidation-reduction status, the biological process of nitrification-denitrification contributed to the overall nitrogen removal up to 99.1%, compared to total nitrogen in the feeding influent. The biological removal of phosphorus that is believed to be the work of phosphorus-accumulating organisms could reach the ranges of 97.7% to 99.3%for total phosphorus (TP) and 69.7% to 98.1% for soluble phosphorus (SP), depending on the ratio of BOD5 to phosphorus in the feeding wastewater. The (AO)2SBR system showed a stable organic matter removal performance. The average removal efficiencies of COD were over 93.9% while nearly 100% of BOD5 was broken down after one cycle of SBR operation. The acetate added along with the primary influent feeding would be more beneficial to improve the nutrients/organic matter removal rates as well as the quality of effluent