This study systematically collected domestic and international research findings on the ecological water level of Poyang Lake. Through visual mapping analysis and statistical analyses, research hotspots, trends, and characteristics were identified, aiming to provide theoretical foundations and practical support for the study and management of Poyang Lake’s ecological water level. First, based on the CNKI (China National Knowledge Infrastructure) and Web of Science Core Collection databases, CiteSpace software was employed for bibliometric analysis to summarize research hotspots and trends in Poyang Lake’s ecological water level. Second, statistical analysis methods were applied to examine ecological water levels across different temporal scales and water level grades. The results revealed that research hotspots focus on three key areas: (1) determination of ecological water levels, (2) impacts of water level fluctuations on wetland ecosystems, and (3) mechanisms underlying the effects of the Three Gorges Dam and climate change on ecological water levels. The field has evolved from hydrological analysis to biological impact assessments, shifted from statistical approaches to model-based methodologies, and presented findings as interval-based thresholds. However, limitations persist, including insufficient data precision and weak linkages between water levels and biological requirements. Future efforts should prioritize enhancing data quality through remote sensing technologies, deepening research on the ecological effects of water level regulation, and promoting practical applications in water resource management. The annual minimum ecological water level was identified as 9.71 ± 1.94 m, while the annual suitable ecological water level was 12.53 ± 2.01 m, both exhibiting substantial variability. At the monthly scale, ecological water demands peaked from July to August and reached their lowest in January. Although trends in ecological water levels derived from different accounting methods were generally consistent, significant variations in the ranges of minimum and suitable ecological water levels were observed across months.