Abstract: In the brow soil, if we use water-keep-matter effectively on sweet potato, its drought-fighting ability will become stronger, the whole seedling weightier, the dry seedling weightier obviously too; caudexes count and the average weight of potato will both increase, production increase rate is 4.6%~31%. In this examination, when the dosage of the water-keep-matter is 45kg/hm2, the production increase effect is the best; point in water-keep-matter or dipping seedling in water-keep-matter solution is indistinctive. But dipping seedling in keep-water-substance is simpler and convenient, and so is advisable.