The present invention discloses a mud-rock flow disaster dangerous case dynamic early warning method. On the basis of river basin investigation and monitoring system real-time data, a two-dimensionaldiving wave equation is employed to perform numerical simulation of mud-rock flow motion along a way, a submerging range and a submerging depth of the mud-rock flow is predicted on a DEM grid level, hazard-affected body data is superimposed to analyze information of degree, affected by the hazard, of a hazard-affected body, safe evacuation lines and the like, and the information is timely published to the population in the basin. The present invention further discloses a mud-rock flow disaster dangerous case dynamic early warning method. Monitoring information influencing mud-rock flow disaster factors is comprehensively obtained and analyzed to allow formation, generation and evolution processes of the whole mud-rock flow as a highly dynamic process to perform prediction and monitoring and perform fine early warning of the mud-rock flow disaster through four steps consisting of pre-disaster prediction, disaster-coming early warning, disaster generation early warning and dangerous casedynamic early warning. Compared to a current one-step and one-index monitoring early warning technology, the method provided by the invention fully combines dynamics features and rules of the mud-rock flow disaster, and is more scientific and higher disaster reduction practicality.