This dataset contains the annual boundary data of Siling CO for the period 1990–2023, extracted using Google Earth Engine based on remote sensing imagery. Siling CO is the largest high-altitude lake in the world and has experienced rapid expansion under the influence of climate warming, glacier melt, permafrost degradation, and changing hydrological conditions on the Tibetan Plateau. The dataset provides a continuous record of lake boundary changes over more than three decades and is intended to support research on lake expansion, shoreline evolution, overflow risk, and hydrological responses to climate change. The dataset was produced for the study “Wind-Driven Overflow Threshold of Siling CO and Its Underlying Mechanisms”. It can be used to analyze the spatial evolution of Siling CO, identify areas vulnerable to overflow, and support hydrodynamic or hazard assessment modeling related to wind-driven lake overflow. The data are suitable for academic research, environmental assessment, and comparative studies of plateau lake dynamics.