Abstract: The Shengjin Lake in Anhui Province is an important wintering habitat for waterbirds in the middle and lower Yangtze River floodplain. As a river-connected lake, the landscape pattern manifests seasonal changes that affects the habitat suitability of waterbirds. This study investigated the change of landscape pattern of Shengjin Lake and the influencing factors, using correlation analysis and regression models, for the period of waterbird wintering season (i.e., from November 2021 to April 2022). Data of remote sensing images of Landsat and GF6, water levels, and meteorological data were collected. Results showed that the water level played a major role in controlling the landscape pattern. In the early wintering period when the water level was below 11 m, the grassland and mudflats area reached the maximum values of 51.6 km² and 14.4 km², respectively. A rising of water level during the middle wintering season led to an expansion of water surface area and a rapid shrinkage of grassland and mudflats coverage, reaching the minimum of 5.6 km² and 8.5 km², respectively. In the late wintering period when the water level was above 13 m, the core area of Shengjin Lake Reserve was dominated by water surface, and the area of grassland and mudflats was less than 5 km²,distributing near the lake bank. The human control in Huangpen Sluice caused a decline of water level in early March, and an associated increase of the coverage of grassland. The findings were further supported by a statistical analysis. At the landscape scale, the water level was significantly positively correlated with the largest patch index and contagion index (p<0.05), while negatively correlated with the patch density and Shannon’s diversity index (p<0.05). Moreover, regression results revealed that precipitation was a major factor affecting the water level of Shengjin Lake (p<0.05). In the middle and late wintering periods, precipitation affected the landscape pattern of Shengjin Lake via its influence on the lake water level. The Reserve Department may regulate the lake water level according to the seasonal changes of the landscape pattern of Shengjin Lake to provide a suitable habitat for waterbirds during the wintering season.