Due to the extensive use of chemical preservatives to increase the shelf life of foods and the prevalence of colorectal cancer, the demand for natural and safe pharmaceuticals and preservatives has increased. Thus, this study aimed to evaluate the antioxidant and cytotoxic potentials of Foeniculum vulgare essential oil, which has vast applications in the traditional medicine. In this study, the essential oil of F. vulgare was extracted by hydrodistillation method and its chemical constituents were identified quantitatively and tentatively using gas chromatography coupled to mass spectrometry and fourier transform infrared spectroscopy. The total phenol and flavonoid contents of the essential oil and its antioxidant activity (DPPH and ABTS free radicals scavenging activity and β-carotene/linoleic acid bleaching inhibition) were also investigated. The cytotoxic effect of F. vulgare essential oil was evaluated on colon cancer cell lines (HT29) using MTT assay. Anethole (75.61%) was the main chemical compound of F. vulgare essential oil and its absorption peaks were appeared at 1244 and 840 cm^-1. The total phenol and flavonoid contents of F. vulgare essential oil were 12.87 mg GAE/g and 39.67 mg QE/g, respectively. The antioxidant capacity of the essential oil, based on DPPH radical scavenging activity, ABTS radical scavenging activity, and β-carotene/linoleic acid bleaching inhibition, were 26.68, 39.57, and 32.38%, respectively. The cytotoxic effect of the essential oil on the colon cancer cells was depended on its concentration. The F. vulgare essential oil could be used as a natural compound to inhibit the oxidation of foods and the prevalence of colorectal cancers.