Extracts of natural plants contain several chemical groups with various biological activities. This work aimed to evaluate the antioxidant, anthelminthic activities and determining the secondary metabolites, mineral and histological elements of Ocimum gratissimum from Democratic Republic of the Congo used for various culinary and therapeutic purposes. Primo Star 200Â® microscope was used for microscopic analysis further thin layer chromatography and X-ray fluorescence were used for chemical analysis. Antioxidant and anthelminthic activities were evaluated with DPPHÂ° radical scavenging method and the rate of Benhamia rosea death, respectively. Spiral vessels, group scleritis, sclerotic fiber, pollen seed, stomata, hairs cells were found by Powder microscopic analysis. Secondary metabolites such as polyphenols (tannins, flavonoids, anthocyanins, leuco anthocyanins), alkaloids, steroids, terpenoids and various mineral elements (K, Ca, Cl, P, S, Mg, Na, Zn, Cu, Mn, Fe, etc.) were found in O. gratissimum leaves. Aqueous extract showed a high antioxidant activity with an IC50 of 25.7 Â± 1.03 Î¼g/mL. Aqueous extract of O. gratissimum leaves is a good antioxidant and it has an interesting anthelmintic activity.