Abstract: In view of the increasingly more serious hazard due to the frequent underground mud-rock slides in metallic mines where caving mining method is adopted, with the process of underground mud-rock slide in Chengchao Iron Mine as the engineering background, a numerical calculation model is built, which composed of ore layer, overlaying layer, water partition layer and mud-rock slide layer.PFC3D numerical simulation software is used in the study of the dynamic process of mud-rock slide.The dynamic evolution process and mechanism of underground mud-rock slide is preliminarily revealed and its mechanical essentials and prevention and control measures that should be taken are summarized.

Key words: Caving mining, Underground mud-rock slide, Occurrence mechanism, Numerical simulation