Cloud point extraction (CPE) of three PAHs, anthracene, phenanthrene, and pyrene was performed in an ultrasonic environment with Tergitol TMN-6 as extractant. During the process, surfactant micelle aggregates came out gradually and deposited to form a surfactant-rich phase. Under the ultrasonic condition, an obvious higher phase separation speed was obtained than the process with heating alone. In the comparison with the conventional cloud point extraction process accelerated by centrifugation, the ultrasonic assisted process offered higher recoveries of the three PAHs with a similar or quicker speed, and relative high recoveries were still preserved even in a high initial PAHs concentration of 60 mg/L. Moreover, the water content in the surfactant-rich phase obtained by the ultrasonic process was lower than that by the centrifugation process when the surfactant concentration was lower than 2wt%, leading to a higher preconcentration factor and treatment efficiency in a continuous water treatment process with CPE. Scaling up experiments of the new developed ultrasonic process were performed in the polluted water with different volumes, and recoveries of 80.4%, 92.6%, or 79.3% for anthracene, phenanthrene or pyrene respectively were obtained in 500 mL polluted water, which indicated the process had a great potential to be used in the water treatment in a large scale.