Abstract: While China’s economy has progressed exceedingly rapidly, its adverse impact on the environment has been overlooked, thus resulting in numerous issues related to environmental contamination, including water resources pollution. The submersible pusher, due to its diminutive size, facile installation process, and excellent maintenance qualities, is capable of being installed within treatment pools of limited volumetric capacity. By enabling enhanced processing efficiency within each pool, this approach facilitates system-wide efficiency without being subject to the limitations of a singular step’s efficiency. During the procedure of wastewater treatment, the submersible mixer plays a paramount role as one of the essential core components. Its performance and function bear a significant impact on the ultimate quality of the entire sewage treatment process. Hence, the subaqueous propeller has emerged as a crucial apparatus that facilitates the process of amalgamating and propelling fluid within sewage treatment facilities. An integration of experimentation and computational fluid dynamics（CFD） numerical simulation is employed to investigate the various performance indicators, including thrust, power, and thrust-to-power ratio of a submersible thruster operating at a rotating speed of 980 r/min and having a diameter of 400 mm. Additionally, a three-dimensional geometric model is established, followed by the conduction of structured mesh delineation and mesh-independence analysis in order to ensure accurate simulation results. Finally, non-stationary calculations are conducted on the submersible thruster using the aforementioned methodology. Through numerical calculations, it is determined that the submersible mixer equipped with the deflector generated a thrust of 759.33 N, consumed 888.29 W of power, and yielded a thrust to power ratio of 0.85 N/W. Conversely, the submersible mixer without the deflector produced a thrust of 1 003.39 N, utilized 1 144.72 W of power, and resulted in a thrust to power ratio of 0.88 N/W. The present study examines the impact of a deflector on a submersible thruster’s thrust, power, and thrust-to-power ratio. Results indicate that the inclusion of a deflector reduces the aforementioned variables by 24.3%, 22.4%, and 2.4%, respectively, as compared to a submersible thruster lacking a deflector. Through the experiment, it is determined that the submersible mixer equipped with the deflector generated a thrust of 740 N, consumed 903 W of power, and yields a thrust to power ratio of 0.82 N/W. Conversely, the submersible mixer without the deflector produces a thrust of 977 N, utilized 1 164 W of power, and results in a thrust to power ratio of 0.84 N/W. The thrust, power, and thrust-to-power ratio of a submersible thruster with a deflector are reduced by 24.3%, 22.4%, and 2.4%, respectively, for a submersible thruster without a deflector.The discrepancy observed in the comparison of the simulated and experimental measurements of thrust, power, and thrust-to-power ratio falls under 5%, hence confirming the reliability of the experimental results and effectively attesting the precision of numerical simulation.The application of a deflector to the thruster has a positive impact on the thruster′s effective propulsive distance. Specifically, when compared to the situation in which a deflector is not applied, the effective propulsive distance increases by 4.8%, 28.4%, and 30.8% at velocities of 0.3, 0.4, and 0.6 m/s, respectively.