The effect of temperature on nutrient removal performance and operation cost with DO control by frequency conversion was investigated during the longterm operation process of treating realistic domestic wastewater with pilotscale SBR process. It is found that the temperature has limited influence on the removal efficiency of COD and PO43-P

while has obvious impact on ammonia removal. Ammonia oxidation rate decreased sharply with the decrease of temperature when the temperature was from 11 to 26℃. Meanwhile

phosphorous uptake and release rate of microorganism almost fixed at normal level under temperature (1826℃) and decreased sharply at temperature (1118℃). Finally

the variation of energy consumption at different temperature was investigated. And the effect of DO control by frequency conversion on the energy consumption of aeration phase was analyzed.