Abstract: By analysis on the monitoring data of face－slab stress and strain, huge compressive stress was found on the face-slab, and the compressive stress at the joints was 8～15 MPa.In the process of storage water level rising, face－slab damage happened which exerted bad influence on the safety and profit of the project.Although rehabilitation, high compressive stress didn’t disappear which called for closer monitoring.Only in this way, dam safety can be guaranteed.