Abstract: Lacustrine ecosystems play a significant role in regional hydrological regulation, biodiversity conservation, and water purification. Their stability is closely associated with the morphological evolution of lakes. Existing studies on the Dongting Lake basin remain insufficient regarding the multi-dimensional quantification and driving factor analysis of the morphological evolution of its subsidiary lakes. This study investigated the representative Datong and Maoli lakes within the Dongting Lake basin based on the Landsat remote sensing images from 2002 to 2022. Specifically, this study analyzed the spatiotemporal evolution patterns of key morphological indicators, including lake area, circumference, near-circularity, length-width ratio, and shoreline development index, and explored their driving factors. Furthermore, this study proposed suggestions on the ecological protection and restoration of lakes within the basin from the perspective of ecological space use control. The results indicate that from 2002 to 2022, Datong Lake exhibited minor area differences between wet and dry seasons, an increase of 14% in its circumference, a continuous drop in near-circularity, and increasing fragmentation of shorelines. In contrast, Maoli Lake displayed a gently varying area, a constantly increasing circumference in the dry season (increasing by 30.4% over the study period), an extremely low near-circularity, and significantly increasing complexity of the shoreline morphology. Climate change and human activities impose distinct effects on shoreline morphology. From the perspective of ecological space use control, the ecological protection and restoration of lakes should be optimized by strengthening the coupling of rigid and flexible regulation, enhancing monitoring and early warning via "one map", advancing cross-regional river basin coordination, and improving the mechanisms for achieving the value of ecological products. This study can serve as a reference for optimizing the ecological protection and restoration of lakes in populated areas.