Ocimum basilicum is an aromatic plant with multiple uses in food, medicine, and cosmetics. This chapter compares the chemical composition and antimicrobial activity of essential oils of Ocimum basilicum from different geographical regions. The study reveals a significant variation in major compounds such as linalool, eugenol, estragole and methyl cinnamate, which are influenced by geography. In the antimicrobial comparative study, hexane extracts showed the most potent antimicrobial activity, particularly against the Staphylococcus aureus strain, with linalool as the main active compound. These results underline the potential of this plant as a natural antimicrobial agent and the importance of optimizing extraction methods.