Vegetables and fruits are well known for their protective effects against oxidative stress because of their antioxidant properties. In the present studies locally available watermelon has been evaluated for its protective effects against paracetamol induced oxidative stress in albino rats. Three doses of fresh water melon extract (2.5ml, 5.0 ml and 7.5 ml per Kg body weight) along with paracetamol (125mg/Kg body weight) have been administred orally to three groups (5 each) of experimental rats for 30 days. Paracetamol control group was administered only paracetamol (125mg/Kg body weight) and normal control group was given equal volume of distilled water.. Rats were killed on day 31 after ether anaesthesia and blood was collected from brachial artery in heparin coated centrifugation tubes. Blood was centrifuged and plasma was separated to measure thiobarbituric acid reactive substances, serum glutamate oxaloacetate transaminase, serum glutamate aspartate transaminase, reduced glutathione, tocopherol, glutathione per oxidase and super oxide dismutase. Results indicate that fresh watermelon extract inhibits lipid peroxidation, boosts the levels of glutathione and tocopherol. It also enhances the activity of super oxide dismutase and glutathione peroxidase. Carotenoid contents of watermelon might be the cause of its protective effects which are absorbed readily from the intestine after its intake. Key words Carotenoids, thiobarbituric acid reactive substance, glutathione, super oxide dismutase, glutathione peroxidase.