The present study was undertaken to evaluate the possible reno-protective effect of Ficus exasperata leaf aqueous extract (FEE) in a rat experimental paradigm of diabetes mellitus. Forty Wistar rats (weighing 200-230 g) were divided into four (A, B, C, and D) groups, each group consisting of 10 rats. Group A rats served as 'control' animals and received citrate buffer (pH 6.3) solution in quantities equivalent to intraperitoneally-administered volumes of streptozotocin (STZ) and FEE. Diabetes mellitus was induced in Groups B and C rats by intraperitoneal injections of STZ (75 mg/kg). Group C rats were additionally treated with FEE (100 mg/kg/day, p.o.) 4 weeks post STZ injections, for 4 consecutive weeks. Group D rats received FEE (100 mg/kg/day p.o.) only for 4 weeks. Post-euthanisation, kidney tissues were excised for histopathological evaluation and processed for light microscopy. Plasma malondialdehyde and tissue nitric oxide were determined. Serum creatinine, blood urea nitrogen, nitrite, and albumin concentrations were measured for the evaluation of renal function. The diabetic rats significantly lost more weight and their blood glucose levels were significantly elevated as compared to the 'control' group of animals. Renal dysfunction was evidenced by kidney hypertrophy, decreased renal blood flow, and increased serum creatinine and nitrite concentrations. Furthermore, vascular dysfunction, as evidenced by decreased carotid blood flow, was observed in the diabetic rats. FEE treatment positively ameliorated the alterations in the biochemical variables in the STZ + FEE-treated rats. In conclusion, our findings suggest that FEE treatment ameliorates STZ-induced nephrotoxicity.