Abstract: It comes the first time for construction of hydropower projects in China for which it is designed of taking riprap to protection dam slope on the upstream in the left and right earth dams of Daguangba dam. Because of the dam slope destruction resulting mainly from typhoon and tropical storms during flood period annually, which average maximum wind speed is up to 17.8m/s, the max fetch length of reservoir being up to 10km, max wind wave of 3.0m, the original design of using general dry stone pitching will not meet the requirement of keeping dam stable. According to the soil materials designed to use in the left and right earth dams, it has certainly shown that using riprap to protect dam slope in the earth dams is adapt to the characteristics of strong settlement, the advantage of big size of block, along with coarseness on the surface and draining well lower the wave runup dramatically, which not only be good for am stability, but also lower the dam crest elevation of 1.0m and reduce the cost and make it economically.