For the problem that the current methods could not meet the practical needs in the field of dynamic characteristic information extraction and watershed disaster early warning, in order to enhance the technology level of characteristics information extraction and dynamic early warning process, an in-depth study was conducted on the core aspects of performance parameters calculation and the implementation of dynamic early warning depending on the typical watershed disaster, the performance parameters calculation method based on Wireless Sensor Network (WSN) was proposed and the algorithm to deal with disaster dynamic early warning information was designed. With the performance parameters sampled data of typical watershed disaster, the simulation analysis of core performance parameters of the watershed disaster was carried out by using Matlab simulation platform. The experimental results show that the proposed algorithm can capture the dynamic core characteristics information of watershed disaster effectively and improve the dynamic early warning indication accuracy of watershed disaster.