Abstract: The land-side slope of a sea embankment would suffer from erosion induced by overtopping and overflow when extreme events such as typhoon and cold wave happen. Previous studies have shown that the protection of the land-side slope of the earthen levees against wave and surge overtopping during large storm surges is of great importance. Recently more attentions have been paid by engineers and researchers to the land-side slope protection. Different types of strengthening systems were introduced to protect the crest and land-side slope of the levees against surge overflow and wave overtopping after Hurricane Katrina. Meanwhile ecological and landscape requirements were put up for coastal engineering construction. As an innovative side slope protection way, reinforced turf has the advantages of fixing the plants, which in turn fix the soil. The reinforced turf protection can strengthen the erosion resistance and meet the requirements of ecological function as well. The scouring resistance of the land-side slope protected by different types of the reinforced turf under high velocity flow parallel to the land-side slope as well as oblique to the land-side slope was investigated by using flume experiments. The samples with different strengthening methods were tested under high speed open flow. After the tests, the erosion of the turf samples was measured. The depths of the erosion of the samples were plotted versus the rates of discharge. Experiment results show that scouring resistance of different types of the reinforced turf are not the same. The reinforcement effects of combined geogrid and three-dimensional geomats are better than those of the geogrid and natural turf. Comparisons are also made between the erosion resistances against the scouring of parallel flow and oblique flow. Scouring oblique to the land-side slope causes worse damage than parallel scouring to the land-side slope under the same flow discharge rate.