Fruit and vegetable by-products are very rich in bioactive components and are found to be a potential source of antioxidants. Hard data says that they have medicinal effect on health. Mango (Mangifera indica L.) is one of the most important tropical fruits whose by-product is rich in phytochemicals. This study was carried out to evaluate the acute oral toxicity (LD50), if any of mango seed kernel flourIt may be suitable for value-added products and nutraceuticals. A total of 9 wistar albino female rats were used in groups of three females for each step. The doses were orally administered with 300, 2000 & 5000 mg/kg body weight as per OECD-423 Guidelines. The treated animals were closely observed for incidence of mortality and clinical signs of intoxication periodically at one hour interval for 24 hours and twice daily for a period of 14 days. No abnormal clinical signs were recorded and none of the experimental animals died during the period of observation. Conclusively, it may be considered safe to use mango seed kernel powder, since it didn’t show toxicity till 5000 mg/kg body weight.