Chemical composition, antioxidant, antimicrobial and cytotoxic activities of Tagetes minuta (TM) essential oil (TMO) and Ocimum basilicum (OB) essential oil (OBO) were examined. The main components for TMO were dihydrotagetone (33.9%), E-ocimene (19.9%), tagetone (16.1%), cis-β-ocimene (7.9%), Z-ocimene (5.3%), limonene (3.1%) and epoxyocimene (2.03%). The main components for OBO were methylchavicol (46.9%), geranial (19.1%), neral (15.15%), geraniol (3.0%), nerol (3.0%), caryophyllene (2.4%). Inhibitory concentrations (IC50) for reactive oxygen species (ROS) and reactive nitrogen species (RNS) scavenging were 12–17 and 200–250 μg/mL of TMO and OBO, respectively. Minimal inhibitory concentration (MIC) against Salmonella typhi,Escherichia coli,Staphylococcus aureus,Bacillus subtilis,Aspergillus niger, and Candida albicans were 150 ± 8, 165 ± 9, 67 ± 8, 75 ± 7, 135 ± 15, and 115 ± 8 μg/mL of TMO, respectively. MIC for S. typhi,E. coli,S. aureus,B. subtilis,A. niger, and C. albicans were 145 ± 8, 160 ± 7, 45 ± 4, 40 ± 3, 80 ± 9, and 95 ± 7 μg/mL of OBO, respectively. IC50 for nasopharyngeal cancer cell line (KB) and liver hepatocellular carcinoma cell line (HepG2) were 75 ± 5 and 70 ± 4 μg/mL of TMO, respectively. IC50 for KB and HepG2 were 45 ± 4 and 40 ± 3 μg/mL of OBO, respectively. Thus, they could be used as an effective source of natural antioxidant and antibacterial additive to protect foods from oxidative damages and foodborne pathogens. Furthermore, they could be promising candidate for antitumor drug design.