Background: Breast cancer is the most prevalent disease among women around the world, and is also the leading cause of death from cancer. Herbal medicine is an actual prehistoric form of healthcare known to mankind. Herbal medicine is being used by people belonging to all the cultures. The present study is based on the antioxidant and anti-cancerous potential of Buchanania lanzan which is also named as Chironji. Buchanania lanzan (chironji) is a tree species which belongs to the family Anacardiaceae and is commercially very useful. Methods: In vitro Antioxidant Activity 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and reducing power assay Result: The total antioxidant activity of Buchanania lanzanin leaves was assessed based on scavenging activity of DPPH free radicals, among them pet ether extract of leaves shows 25.54 % inhibition at conc. of 20 μg / ml and at 100 μg / ml it shows 38.95 % inhibition. Ethyl acetate extract at 20 μg/ml it shows 38.41% inhibition and at 100 μg/ml it shows 50.36% inhibition. In methanolic extract at 20 μg/ml it shows 34.42% inhibition and at 100 μg/ml it shows 57.43% inhibition. The IC50 value is defined as the concentration of the substrate that causes 50 % loss of the DPPH activity. Reducing power assay of Petroleum ether extracts, ethyl acetate extract and methanolic extract of Buchanania lanzan was studied at different concentrations and found to be increase with increase in concentration. Conclusion: Therefore, present study concludes that Buchanania lanzan is an excellent medicinal plant which holds numerous bioactive phytochemicals and it can be used in prevention of cancer