从影响土坡稳定的主要因素——强度参数c，φ出发，建立考虑数值变化的定值模型、建立考虑变异性及互相关性的随机变量模型和建立考虑自相关性的随机场模型，采用简化毕肖普法和Rosenbleuth法，着重研究强度参数c，φ对土质边坡可靠度指标的影响。从研究成果中并获得了一些可供工程设计借鉴的有益结论：c对土坡稳定影响较小，但φ在边坡稳定的计算中是最敏感的因子，其数值和变异性对安全系数和可靠度指标计算结果影响很大，在作计算时要求所提供φ的数据应更为精确；在实际工程计算中未考虑强度参数c，φ的互相关性和自相关性得到的可靠度指标较实际工程中的要小，是偏安全的，可作安全储备。

For studying the impact of two main factors, strength parameter c and φ, of soil slope stability on reliability index, three calculation models, i.e., fixed value model, random variables model and random field model, were established, which consider the change of numerical value, the reliability and cross correlation and auto correlation of soil parameters respectively. The Bishop method and Rosenbleuth method are adopted to study the effect of strength parameters on reliability index of soil slope. Several conclusions are drawn as follows: The strength parameter c has little effect on soil slope stability; the strength parameter φ is the most sensitive factor in the calculation of soil slope stability, and its value and variability have the great impact on the results of factor of safety and reliability index. So the provided data of φ should be more precise in calculation. Without considering the cross-correlation and auto correlation of strength parameters c and φ, the result of reliability index is much smaller than the real one in the practical project calculation, and its difference may be served as the safety reserve.