As the traditional deterministic back analysis methods fail to consider the influence of randomness and uncertainty of geotechnical parameters on the slope stability,a new parameter back analysis method with simplicity and practicality,which combines the upper bound method of limit analysis with the reliability theory,is proposed.Then,the feasibility and effectiveness of the proposed method are verified through an engineering application case.The results show that the proposed method not only takes into account the uncertainties and instability of the geotechnical parameters but also helps to implement the back calculation of the shear strength parameters of a slid- ing surface.Meanwhile,the effects of the correlation of shear strength parameters on the back analysis results and the reliability are analyzed,finding that ignoring the mutual-correlation between parameters may lead to a conserva- tive reliability index.