Based on the water quality characteristics of circulating cooling sewage of power plants, which are low organic matter and high nitrogen and phosphorus concentrations, a combined process of SBOT, clarification, sand filtration, ozone oxidation and activated carbon adsorption was applied for full-scale experiments. Under the conditions that hydraulic residence time (HRT) of SBOT=4.5 h, dissolved oxygen (DO) in aerobic zone=3.0 mg/L and C/N is about 2, the results of experiments show that the upward-flow velocity is 1.93 m3/(m2·h), the dosage of polymeric aluminum ferric sul⁃phate (PAFS) is 35 mg/L, the dosage of PAM is 0.2 mg/L, the filtration rate is 8.2 m/h, the dosageof ozone is 55 mg/L, the contact time is 30 min, and the filtration rate of activated carbon filter is 6.8 m/h. The maximum, minimum and average concentrations of CODCr are 12.9 mg/L, 7.6 mg/L and 10.8 mg/L, respectively. Those of NH+4-N are 0.86 mg/L, 0.12 mg/L and 0.47 mg/L, respectively. Those of TN are 8.8 mg/L, 6.2 mg/L and 7.7 mg/L, respectively. Those of TP are 0.21 mg/L, 0.08 mg/L and 0.15 mg/L, respectively. Those of SS are 2.4 mg/L, 0.5 mg/L and 1.7 mg/L, respectively. The average removal rates of CODCr, NH4+-N, TN, TP and SS are 64.4%, 97.2%, 75.7%, 54.7% and 91.9%, respectively. The effluent concentrations of those pollutants satisfy the requirements of Discharge standard of major water pollutants for municipal wastewater treatment plant (DB33/2169—2018).