Abstract: As a core component in fields such as sewage treatment, submersible pumps' energy consumption directly affects the green development of the industry. This paper reviews the classification and research progress of energy-saving technologies for submersible pumps, with the core technology system covering three major directions: hydraulic optimization, motor energy saving, and intelligent control. Hydraulic optimization takes impeller structure and the matching of overcurrent components as the key path, and achievements such as cutting impellers have improved efficiency by 8% compared to national standards. Motor energy saving has formed a system of efficient motor selection, frequency conversion control, and pump matching, with permanent magnet synchronous motors improving efficiency by 5%～10%, and frequency conversion control achieving energy savings of 10%～30%. Intelligent control integrates algorithms such as PID and neural networks, with fault diagnosis accuracy exceeding 90%. Studies have shown that existing technologies have significant results, but there are problems such as insufficient adaptation to complex working conditions, lack of multi-technology synergy, and high initial costs.Future efforts should focus on enhancing the synergy of flow passage components, developing low-cost motors, and promoting the integration of multiple algorithms with digital twins to construct a comprehensive energy-saving system for all operating conditions, thereby facilitating the low-carbon upgrade of environmental protection equipment.