Plectranthus vettiveroides is widely distributed throughout the Sri Lanka. The plant is used as folk medicine in the treatment flatulence, liver disease and jaundice. The plant has bitter taste, cold potency and pungent resultant. The present study was carried out to evaluate the antipyretic potential of infusion from the root powder of Plectranthus vettiveroides. Female and male Wistar rats of with body weight 230-250g were used. Which is divided in to 3 groups, in each contains 3 animals. Rats were familiarized to laboratory conditions for four days before the commencement of experiment. Fever was induced by sub cutaneous injection of 15% Brewer's solution (2.5ml) in the nape of the neck. 18 hours after the giving of fever induced drug, rectal temperature was measured. Then the measurement was repeated after 30 minutes. After that infusion of root powder of Plectranthus vettiveroides (0.5ml) was orally administered to the test group, 0.5ml of normal saline (0.9%) for control group and 0.5ml of Paracetamol for standard group. After animal received the test compound or the standard drug by the oral administration, the rectal temperatures were recorded again 30, 60,120 and 180 minutes. Single dose administration of test drug produces significant antipyretic effect in Brewer's induced fevered rats. The root powder of Plectranthus vettiveroides showed significant reduction in the elevated body temperature of rat which was compared with standard Paracetamol. The results suggest that the infusion of leaf powder of Plectranthus vettiveroides possess antipyretic activity and can be used as potent natural antipyretic drug.