The invention discloses application of a cyclic erythropoietin-derived peptide in protection of renal injury and cyclosporine A injury. In a control group, the abdominal cavity and renal pedicle are exposed; in IR, two renal pedicles are separated, and are clipped with a vessel clamp for 30 minutes to enable color of the kidneys to be changed, and refilling is performed for 2 or 8 weeks; in IR plus CsA, CsA is dissolved in olive oil, and IR mice are subjected to intragastric administration every day; in IR plus CHBP, CHBP is dissolved in saline water, and the IR mice are subjected to intraperitoneal injection every three days; in IR plus CsA plus CHBP, CsA and CHBP are used for treating the IR mice at the same time; urine albumin/creatinine, serum creatinine, histology, apoptosis, caspase-3 and HMGB1 are evaluated, and intracellular signal channels are screened through a protein chip; and a renal epithelial cell model is established, renal injury is simulated, and the influence of CsA,CHBP and/or caspase-3 siRNA on TCMK1 is studied.