Treatment of renal ischemia-reperfusion (IR) injury with recombinant human erythropoietin (rhEPO) reduces acute kidney injury and improves function. We aimed to investigate whether progression to chronic kidney disease associated with acute injury was also reduced by rhEPO treatment, using in vivo and in vitro models. Rats were subjected to bilateral 40min renal ischemia, and kidneys were studied at 4, 7 and 28 days post-reperfusion for renal function, tubular injury and repair, inflammation and fibrosis. Acute injury was modulated using rhEPO (1000 or 5000IU/kg, intraperitoneally) at time of reperfusion. Renal tubular epithelial cells or fibroblasts in culture were subjected to hypoxia or oxidative stress, with or without rhEPO (200IU/mL), and fibrogenesis studied. The results of the in vivo model confirmed functional and structural improvement with rhEPO at 4 days post-IR (p<0.05). At 7 days post-IR, fibrosis and myofibroblast stimulation were increased with IR with and without rhEPO (p<0.01). However, at 28 days post-IR, renal fibrosis and myofibroblast numbers were significantly greater with IR plus rhEPO (p<0.01) compared with IR only. Mechanistically, rhEPO stimulated pro-fibrotic transforming growth factor-β, oxidative stress (marker 8-hydroxy-deoxyguanosine), and phosphorylation of the signal transduction protein extra-cellular signal regulated kinase. In vitro, rhEPO protected tubular epithelium from apoptosis, but stimulated epithelial-mesenchymal transition and also protected and activated fibroblasts, particularly with oxidative stress. In summary, although rhEPO was protective of renal function and structure in acute kidney injury, the supraphysiological dose needed for renoprotection contributed to fibrogenesis and stimulated chronic kidney disease in the long-term.