BACKGROUND: Urinary oxalate and citrate are the keyfactors in caox urolithiasis of cats and Gamma GlutamylTransferase is a good test for assessment of kidney damage.Favorable effects of Cynodon dactylon on calcium oxalate stoneformation have recently been proved in rats. OBJECTIVES: Thepresent study was designed to investigate the alteration ofurinary oxalate, citrate, and GGT after administration of thehydroalcoholic extract of Cynodon dactylon to experimentalhyperoxaluric cats. No scientific study has been done so far todemonstrate the beneficial effect of this plant in cats. METHODS:13 mature male cats were randomly divided into 3 groups: groupAreceived standard diet and drinking water while, group B andC also received ethylene glycol at sub-toxic dose (130 mg/kg)daily for 30 days. Group C received hydroalcoholic extract ofC.dactylon (400 mg/kg) from day 0 to 30, as well. Urine sampleswere collected on days 0, 15, and 30 and were analyzed foroxalate, citrate, and GGT levels. RESULTS: Urine oxalate levelin group B was significantly higher than group C on days 15 and30. Urinary citrate excretion was significantly higher in group Ccompared to the other groups on day 15; however, it decreasedduring the entire experiment in groups B and C. Urinary GammaGlutamyl Transferase level was increased in hyperoxaluric catsand decreased in the treated group during the experiment.CONCLUSIONS: Based on our results, C.dactylon extract couldreduce the hyperoxaluria and has beneficial effects onpreventing the renal damage in cats. Such findings provide ascientific explanation for applying C.dactylon in prevention andpossible treatment of CaOx kidney stones in cats and humans.