Abstract: In order to enhance the removal rate of phosphorus and nitrogen during the operation of A²O systems, the addition of polymeric aluminum-iron (PAFC) at the front and end of the aeration tank was studied via the construction of a lab-scale A²O reactor. Experimental results demonstrated that the addition of PAFC at the end of the aeration tank showed a much higher TP and NH₄⁺-N removal efficiency compared with addition at the front of the tank, but it showed a lower removal efficiency of NO₃^--N. The optimal PAFC dosage was 4 mg/L at the end of the aeration tank, which would lead to effluent contents of COD_Cr, TN, NH₄⁺-N and TP of 19.8,5.3,6.1 and 0.2 mg/L, representing removal rates of 93.3%, 64.6%, 83.6% and 97.6% respectively. In addition, PAFC showed a higher removal ability of TP and NH₄⁺-N, especially for operation at low temperatures.