提出了大跨度采场围岩突变失稳的两种形式 :构造控制型失稳和能量控制型失稳。对前者 ,提出了基于块体理论的可靠度分析理论和系统突变失稳预测方法 ;对后者 ,以突变论为理论依据 ,利用有限元分析与可靠度分析中的响应面方法相结合 ,建立了围岩突变失稳预测的可靠度分析方法。提出的预测方法应用于西石门铁矿采场失稳预测 ,获得较满意的结果 Two kinds of failure modes of rock mass in large span stope are proposed: structural control instability and energy control instability. For the former, the theory of reliability analysis based on block theory and the method of system instability prediction are proposed. Based on the theory of catastrophe, the latter method is combined with the method of response surface analysis in reliability analysis Reliability Analysis Method for Prediction of Sudden Change in Surrounding Rocks. The proposed prediction method is applied to the prediction of instability in the West Shimen Iron Mine stope and obtains satisfactory results