On 12 May 2008, an earthquake of magnitude 8.0 on the Richter scale occurred at Wenchuan in China. Zipingpu dam also experienced the earthquake. The maximum ground acceleration near the top of the 156 m high rockfill dam exceeded 2 g. The right dam abutment slope, which accommodates all the discharge facilities, remained intact after this severe earthquake. However, the natural slopes on the opposite side of the reservoir were severely damaged. It has been found that the reinforcement provided by more than 1000 prestressed cables in the right abutment slope helped to stabilize it. Measurements from multipoint extensometers and load cells installed in the slope showed that there were sudden changes in displacement and stress during the earthquake. This is clear evidence that reinforcement with anchored cables can be successfully used to stabilize a slope.