Hydrological and water resource monitoring are pivotal components of Earth observation systems, crucial for supporting the high-quality development of water conservancy in the modern era, fulfilling the requirements of “three water” co-governance, and implementing the “sixteen words” water-control strategy. Satellite remote sensing offers a scalable, rapid, and high-precision data acquisition pathway. Nonetheless, challenges persist in the application of existing satellite remote sensing in hydrology and water resources, including difficulties in achieving multi-satellite synchronous observation, limited emergency response capability, and susceptibility to adverse weather conditions. In December 2022, NASA launched the Surface Water and Ocean Topography (SWOT) satellite, the first satellite in the world designed to observe global land and ocean water resources through multisensor collaboration. This groundbreaking satellite greatly improves the spatial and temporal resolution and accuracy of hydrology and water resource monitoring. This study systematically reviews the development status, applications, and technical challenges of hydrological and water resource monitoring satellites. It also analyzes the satellite parameters, scientific tasks, algorithm flow, and application products of SWOT, providing a valuable reference for future satellite design planning and key data processing technologies, especially in China.