The medicinal plants serve as an important component of the health care system in Nigeria. A large number of medicinal plants and purified constituents have shown beneficial pharmaceutical potentials. The quantity of phytochemicals present in different plants differs from one another. Therefore, the present study is to focus on the antioxidants properties of the leaves of some commonly consumed fruit tree in Nigeria which include Mango and Cashew leaves. The antioxidants potential of the leaf extract was examining by determine the Tannin content total flavonoid content total phenolic content hydrogen peroxide scavenging activity and reducing power activity. The result from this study shows that Cashew leaves has the highest phytochemical contents (24.50mg/100g) flavonoid (25.80 mg/100g) and phenolic (29.58mg/100g) content respectively compared to Mango leaves with phytochemical contents tannin (23.89 mg/100g) flavonoid (20.75 mg/100g) and phenolic (11.44 mg/100g) content respectively. Also the result shows that Cashew leaves have the highest reducing power activity and hydrogen peroxide scavenging activity compared to Mango leaves. The order of decrease in reducing power is Cashew>mango. Owing to the antioxidants activities exhibited by these leaves extracts they could be considered as a natural herbal source of antioxidant materials that could be utilized in the food and pharmaceutical industries.