The invention discloses the application of dioscin to the preparation of a renal injury protection medicament. Dioscin has a renal injury protection effect, and can be used for preparing the renal injury protection medicament. Dioscin has an obvious lowering effect on NO (Nitric Oxide), TNOS (Total Nitric Oxide Synthase), iNOS (Inducible Nitric Oxide Synthase), MDA (Malondialdehyde), BUN (Blood Urea Nitrogen) and SCr (Serum Creatinine) rise caused by renal injury, has an obvious increasing effect on the reduction of SOD (Superoxide Dismutase), GSH (Glutathione), GSH-Px (Glutathione Peroxidase) and CAT (Catalase) relative to a Model group, and is dose-dependent. After the intervention of dioscin, the phenomena of large-area renal tubular epithelial cell swelling, brush border disappearance, degenerative necrosis of a part of epithelial cells, blockage of lumens by necrotic and exfoliative cellular debris and the like, which are caused by renal injury are obviously alleviated. Dioscin can be used for preparing a medicinal preparation as an active ingredient according to clinical medication needs. Dioscin has the advantages of safety (no toxic or side effects), effectivity, economy, practicability and the like.