Understanding wetland change is critical to establishing and implementing international conservation and management conventions. With such knowledge, supporting sustainable development, making management decisions, improving policies, and conducting scientific research become possible. However, consistent information on changes in Chinese wetlands has been unavailable. We applied the hybrid object-based and hierarchical classification approach to ∼53,000 scenes of Landsat images acquired between 1980 and 2020 and created a national wetland mapping product (China_Wetlands) for six periods (e.g., 1980, 1990, 2000, 2010, 2015, and 2020). China_Wetlands revealed diverse changes in Chinese wetlands and their trajectories in response to climate change and human impacts over the past four decades. Specifically, there was a substantial shrinkage in wetland area before 2015, with a small rebound between 2015 and 2020. The net loss was ∼60.9 × 10