The invention discloses an impeller aerator with ozone sterilization function. The impeller aerator is characterized in that a floater (1) is connected with a support rod (2), a gear box (7) and an ozone generator (4) are arranged on the support rod (2), a suction chamber (10) is fixed below the gear box (7) through a fixing rod (9), a motor (6) is arranged above the gear box (7), an air outlet which is formed on the ozone generator (4) is connected with an air pipe (5), the air pipe (5) is connected with the interface of the suction chamber (10), an output shaft (8) of the gear box (7) is connected with an impeller shaft (11) through a flange, the impeller shaft (11) passes through the suction chamber (10), and an impeller (12) is arranged at the bottom of the impeller shaft (11). The impeller aerator with ozone sterilization function is sterilization and aeration equipment integrating ozone techniques and impeller aeration techniques, serves the functions of ozone generation, impeller aeration and ozone transfer, achieves the purposes of sterilization, disinfection, aeration and purification, and is advantageous in high efficiency and low energy consumption.