The present study was undertaken to determine diuretic activity of boerhaaviadiffusa root extract in rats. In this study the extraction process was carried out for 18 - 20 h till the appearance of colourless solvent in the side tube. The extract collected was dried by evaporating the solvents on a water bath maintained at <500C and percentage yield of alcoholic extract was recorded with respect to the total quantity of powder used for the extraction. Phyto-chemical evaluation for the extract was performed using standard procedures Results showed that single dose administration of alcoholic extract of roots of Boerhaaviadiffusaas 100,200 and 300 mg/Kg and standard Furosemide (10 mg/kg) have increased the urinaryoutput along with an increase in concentration of Sodium, Potassium and Chloride ions in urine.Alcoholic extract of roots of Boerhaaviadiffusamg/Kg produced a greater diuretic activity whichis comparable to that of standard Furosemide (10 mg/kg). In traditional medicine the plant isused for its diuretic activity. This study come up with identification of so many phyto constituentsreported earlier for this diuretic effect in alcoholic extract of roots of Boerhaaviadiffusa. Thus thestudy supports and justifies the rationale behind the use of roots of Boerhaaviadiffusaits diureticactivity.