Abstract: Based on the analysis of rainfall data, this paper summarizes some key technologies of debris flow automatic real-time monitoring and early warning, and presents a solution and a system for real-time monitoring and early warning of debris flow based on rainfall process.Rainfall intensity and cumulative rainfall are the main parameters for the early warning of debris flow.Methods to correctly identify a rainfall process are of great significance for improving the accuracy of debris flow monitoring and early warning.Combined with the characteristics of the rainfall data, and the criterion of the classification of a rainfall process presented by Jan, the automatic recognition of the rainfall process is realized with the database technique.Due to the influence of the rain gauge operating mode, the time interval of the original data is random.It cannot be directly used for the calculation of the early warning model.Therefore, the rainfall data need to be treated at equal intervals.In the process of early warning, the task to achieve early warning process without manual intervention completely automatic, real-time and stable operation has been a difficult problem of early warning work.This solution introduces the "system services" technology.The entire early warning system is as a system-level background service running on the server to ensure the stable operation of the whole process of early warning and to achieve a true sense of the automatic real-time process of monitoring and early warning of debris flow.The results of this study are applied to the monitoring and early warning of debris flow in Zoumaling gully, which successfully predicted the debris flow events in July 8, 2013.