Kidneys are complex organs, which perform several important functions. Though the formation of urine is their most obvious role, but they also perform the vital co-ordination of water and salt metabolism, acid-base balance and secretion of hormones. The effects of occupational or therapeutically exposure to toxic metals on kidney have been known for many years. A large number of chemicals in common usage are potential nephrotoxic viz. Glycols (plastics solvents), paints, lacquers, cosmetics and flavouring extracts. The nephropreotective activity of the poly herbal formulation (composed of the extracts from Terminalia chebula, tinospora cordifolia, Phyllanthus emblica, Portulaca oleracea) was evaluated in Gentamicin induced nephrotoxicity in rats, Gentamicin like other aminoglycoside antibiotics causes nephrotoxicity by inhibiting protein synthesis in renal cells. The serum creatinine and blood urea nitrogen (BUN) were found to be significantly increased in rats treated with only gentamicin, whereas treatment with PHME the effect of gentamicin indicating nephroprotective activity. Among various doses, 200mg/kg, 400mg/kg has shown good nephroprotective activity.