The essential oil from the leaves of Tagetes minuta L., growing wild in Yemen, was obtained by hydrodistillation and analyzed by gas chromatography–mass spectrometry. A total of 28 compounds were identified representing 74.2% of total oil composition. Major components of the essential oil were (Z)-ocimenone (15.9%), (E)-ocimenone (34.8%), (Z)-β-ocimene (8.3%), limonene (2.3%), (Z)-tagetone (1.8%), dihydrotagetone (1.4%) and an unidentified dimethylvinylketone derivative (20.6%). The oil showed moderate cytotoxic activity against MCF-7 breast tumor cells, with an IC 50 of 54.7  6.2 μg/mL. In the DPPH radical scavenging assay, T. minuta oil showed potent antiradical activity with an IC 50 value of 36 µg/mL. Antimicrobial activity was also investigated on several microorganisms, and the essential oil exhibited high activity against methicillin-resistant Staphylococcus aureus (MRSA) with an inhibition zone of 23 mm. It also exhibited remarkable antifungal activity against Candida albicans with an inhibition zone of 26 mm. In recent decades, the essential oils of aromatic plants have been of great interest as sources of bioactive natural products [1]. Antioxidants act as free radical-scavengers and either inhibit or slow down lipid peroxidation and other free radical-mediated processes. Therefore, they have a tendency to protect the body from various disorders which are attributed to free radicals such as cancer, arteriosclerosis, malaria, rheumatoid arthritis, neurodegenerative diseases and aging processes by protecting the organism against oxidative damage [2]. On the other hand, new sources of antimicrobial agents need to be discovered due to the existence and continuous evolution of resistant microorganisms, such as methicillin-resistant Staphylococcus aureus (MRSA). Around 90–95% of S. aureus strains world-wide are resistant to penicillin and in most Asian countries about 75% of the same bacterial strains are methicillin resistant [3,4] Essential oils and their volatile constituents have been widely used for bactericidal, fungicidal, spasmolytic, carminative, hepatoprotective, antiviral, antiparasitic, insecticidal, anticancer, antioxidant, antidiabetic, cardiovascular, and cosmetic and food applications [5-8]. Tagetes is a genus of 56 species [9] of annual and perennial, mostly herbaceous, plants in the Asteraceae. This genus is recognized as a source of carotenoids used as food colorants and feed additives [10], and for possessing anticancer and anti-aging effects [11],