Through the large-scale model test of cemented earth dam, the velocity distribution and the dam erosion process of cemented earth dam under the flood overtopping were analyzed to verify the feasibility of non-failure overtopping of cemented earth dam. The test results show that the unconfined compressive strength of cemented soil within the model is more than 4.MPa after 28 days. When the maximum water head at the crest of cemented earth dam is 55.cm, the downstream slope ratio is 1∶2 and the maximum velocity reaches 5.6.m/s, there is no collapse failure after the overtopping scouring for 44.h. After the overtopping scouring, the maximum erosion depth of downstream dam slope is 10.cm and the average erosion depth is only 1.07.cm, thus the cemented earth dam can effectively prevent the collapse caused by the overtopping scouring of flood.