Abstract: Stability evaluation of high and steep slopes, which are created by the gravity anchorage block foundation excavation,is one of key problems in the safe construction of the bridge and the safe operations of the bridge after construction. This paper presents a case history of the slope stability evaluation on the slope at the gravity anchorage block of Taoyuan Jinshajiang River Crossing Bridge of DaYong Expressway project in Yunnan Province. The slope stability evaluations were performed using finite element method, limit equilibrium method and Newmark analysis method with the sitespecific soil and rock parameters from the geotechnical borings and site reconnaissance results and under design seismic conditions. The results indicate that, the potential sliding plane gradually moves from the back area to the front area. Under the seismic loading conditions, the permanent deformations can be divided into three zones: linear increase zone, acceleration zone and deformation failure zone. The slopes of anchorage blocks are unstable under the earthquake intensities Ⅷ & Ⅸ. The slopes stabilized with prestressed rock anchors can improve the seismic behavior of these slopes.