The wistar strain male albino rats were fed with various seabuckthorn products for a period of 30 days, to determine the bioavailability of antioxidants in seabuckthorn based products (juice powder, jam, squash and fruit yoghurt) and concurrent effect on antioxidant system in rats. The excretion of antioxidants in urine and feces; availability of antioxidants in blood and tissues of liver, heart and kidney; Melondialdehyde (MDA), Glutathione in reduced form (GSH) and antioxidant enzymes such as catalase and superoxide dismutase (SOD) were determined in triplicate. The level of antioxidants in seabuckthorn juice powder were significantly (p<0.05) greater than jam, squash and fruit yoghurt. Results also proved that the level of antioxidants in seabuckthorn based products was directly proportional to bioavailability which significantly improved antioxidant system in rats by reducing MDA; increasing the GSH, catalase and SOD levels. Thus the seabuckthorn based products were considered to be an antioxidant rich food source to prevent degenerative diseases.