In the present investigation, Strychnos nux-vomica, an important plant used in traditional medicine, was evaluated for its antioxidant potential. The antioxidant potentials were examined in terms of non-enzymatic antioxidant molecules and activities of antioxidant enzymes. The non-enzymatic antioxidant molecules studied were ascorbic acid, ⍺-tocopherol and reduced glutathione. The estimated antioxidant enzymes were superoxide dismutase, ascorbate peroxidase, catalase, peroxidase and polyphenol oxidase. The analyses were carried out in the field-collected leaf samples. It was found that plant contained a significant quantity of non-enzymatic and enzymatic antioxidants in the leaves. These findings have high significance in the pharmacological industry; however, a detailed investigation is needed to confirm this conclusion, by radical scavenging ability, which is underway in our laboratory. To cite this article: R. Vijayakumar et al., C. R. Biologies 332 (2009).