Sesamol has been shown earlier to exhibit antimutagenic (reactive oxygen mediated) and antiageing activity in our lab and it has also been found to exert chemopreventive effect. Here we report the in vitro antioxidant activity of sesamol. As most of the antioxidants act due to their property to auto-oxidise and the pro- or antioxidant activity would depend on the concentration of the agent used and the free radical source, at least 6 dilutions in concentration range of 5-1000 nmoles of sesamol were selected for each test system. Further the antioxidant activity was compared with a water soluble antioxidant (ascorbic acid). Eventhough some preliminary studies on the antioxidant activity of sesamol have been reported in DPPH assay & inhibition of lipid peroxidation, it is not complete. We, here in report comprehensively (both in terms of the no. of doses and also a variety of test systems being employed) on the antioxidant activity of sesamol. Furthermore, since all the data has been generated by the same workers and under same laboratory conditions, hence is scientifically significant. Also the process of dose selection as discussed earlier is more scientific; and the data treatment, i.e. calculation of IC(50) values and comparisons with ascorbic acid has been statistically validated. In conclusion, sesamol was found to be an efficient scavenger of the entire range of ROS in several test systems pointing towards the potential of sesamol to be developed as a possible therapeutic.