The diuretic activity increases the rate of urine flow, sodium excretion and to maintain the volume and composition of body fluids in a various clinical disorders such as congestive heart failure (CHF), chronic renal failure, nephritis, cirrhosis, hypertension and pregnancy-induced toxaemia. Many studies regarding herbal plant used in traditional medicine as diuretics are nowadays used for treatments. The aim of the present study was to evaluate the diuretic activity of the ethanolic extract of Justicia Gendarussa (Burm) f. Plant leaf to provide evidence about its diuretic activity. The diuretic responses with its electrolyte excretion potency of the J. gendarussa (Burm) f. ethanolic extract are highly moderate in comparison to normal control rats. The J. gendarussa (Burm) f. ethanol extract at doses of 400 mg/kg showed a significant increase in Na+, K+ and Cl- excretion. The results of urinary electrolyte excretion after treatment of J. gendarussa (Burm) f. ethanol extract were comparable to the furosemide group. Finally increased total urine volume and the urine concentration of Na+, K+ &Cl- will be the evidenced for the diuretics of Ethanol extract of Justicia Gendarussa (Burm) f. Plant leaf and deserves further studies considering the potential for the treatment of hypertension.