Abstract: Hydrological data processing is a crucial fundamental work that supports fields such as flood and drought disaster prevention and water resources management. It is of great significance for ensuring the reliability, integrity and availability of hydrological data. This paper systematically reviews the development history of hydrological data processing in China in terms of timeliness, methods, approaches and code. Regarding future development, it is proposed that hydrological data processing will achieve real-time processing in terms of timeliness and move towards intelligence, realizing the optimization of the entire data processing process through the construction of intelligent agents. In terms of approaches, it will explore new paths for intelligent flow calculation with the help of AI technology. At the same time, hydrological forecasting, monitoring, and processing will be deeply integrated. Relying on technologies such as the Internet of Things and digital twins, an intelligent system covering the entire chain will be formed, providing stronger support for digital twin water conservancy, the enhancement of Four Pre-capabilities, as well as scientific research, management and decision-making in hydrology and water resources.