The ethanolic extract of Boerhaavia diffusa root was tested for diuretic and antiurolithiatic activities. The parameters considered for diuretic activity were total urine volume and urine electrolyte concentrations like Na+, K+, HCO3- and Cl-. The ethanolic extract was administered orally to the experimental rats at a dose of 250mg/kg and 500 mg/kg. Furosemide (5mg/kg) and cystone (750mg/kg) were used as reference standard for diuretic and antiurolithiatic. The rats treated with ethanolic root extract showed increased urine output when compared to the control. The extract showed increased excretion of electrolytes when compared to control. Urolithiatic activity was induced in rats by using 0.75% of ethylene glycol in drinking water for 28 days. The parameters such as oxalates, calcium and phosphate in urine and serum creatinine, calcium and uric acid were estimated. Treatment with the ethanolic root extract of Boerhaavia diffusa restored all biochemical and urinary parameters. In In-vitro antiurolithiatic activity Calcium oxalate crystallization was induced by the addition of 0.01M sodium oxalate solution in synthetic urine. The effect of extract (100, 300 and 500 μg/ml) was studied by time course measurement of absorbance at 620 nm for ten minutes by using spectrophotometer. Ethanolic root extract at 100, 300 and 500 μg/ml concentration of extract showed inhibition at 120 sec (50.20, 62.68 and 71.64 %), and maximum inhibition of the crystallization of calcium oxalate at 600 seconds (69.38, 74.14 and 82.99 %). The results indicate that the ethanolic root extract of Boerhaaviadiffusa is endowed with diuretic and anti urolithiatic activities.