Objective(s): It has been shown that adipose-derived mesenchymal stem cells (AD-MSC) have protective effects in acute kidney injury (AKI). This study was conducted to assess the therapeutic effects of AD-MSC in rats subjected to acute kidney injury by 45 min of renal ischemia followed by 48 hr of reperfusion (I/R). Materials and Methods: 28 male Wistar rats were divided into four groups, including control, 48-hr sham, 48-hr I/R, and 48-hr I/R receiving AD-MSC. After 48 hr of reperfusion, blood samples were taken from rats’ hearts, and 24-hr urines were collected using a metabolic cage. Serum creatinine level (Cr), blood urea nitrogen (BUN), creatinine clearance (Ccr), absolute sodium excretion (UNaV°), fractional sodium excretion (FENa), absolute potassium excretion (UKV°), factional potassium excretion (FEK), and urine osmolarity were measured. Malondialdehyde (MDA) and ferric reducing antioxidant power (FRAP) levels were measured in the right kidney, while the left kidney was used for histologic study after Hematoxylin-Eosin staining.Results: Renal I/R significantly increased serum Cr, BUN, UNaV°, FENa, FEK, and tissue MDA, and significantly decreased Ccr and urine osmolarity as compared with the sham group. Moreover, histologic studies showed that I/R increased Bowman capsule area, tubular necrosis, vascular congestion, and caused formation of intratubular casts. Administration of AD-MSC at the time of I/R completely or partially protected kidneys from these I/R induced injuries.Conclusion: Our results show that injection of AD-MSC can reduce degree of renal injury caused by 45 min of ischemia followed by 48 hr of reperfusion in rats.