Living cells are under continuous siege in oxidative stress, which are believed to result in a variety of human health disorders. Ionizing radiation induced oxidative damage in membranes and cells are suggested to be mediated through generation of reactive oxygen species (ROS). Therefore, intake of antioxidants credited with phytochemicals is considered consequential for the ability of cell to cope with the stress related cellular responses. Present study was aimed to evaluate the radioprotective ability of one of the popular ayurvedic herbal drug, Swertia chirata (Sc) that is believed to possess several medicinal properties. Experiments conducted on the oxidative damage in liver subcellular organelles of laboratory animals ex vivo and in vivo have shown that aqueous extract of Sc (~50 µg/ml) significantly prevented the cellular damage in terms of lipid peroxidation, protein oxidation, antioxidant enzymes and single strand breaks in plasmid pBR322 DNA after radiation exposure. The radioprotective action of Sc was found dependent on its concentration. In addition, studies on biochemical assays for evaluation of antioxidant enzyme, SOD showed remarkable restoration by Sc in irradiated liver of mice in vivo (2 Gy). This paper presents a brief review of role of herbals in radioprotection with an emphasis on our results concerning the mechanism of protective action of Sc on irradiated organs and cells.