摘要:Background: Zataria multiflora Boiss. is known by the common Persian name “Avishan-e-Shirazi”, is one of the best-known medicinal herbs belonging to the Labiatae (Lamiaceae) family. The aim of this study was to evaluate the anticancer effects and the underlying mechanisms of how Z. multiflora Boiss., essential oil induced apoptosis in the human colorectal tumor cell lines (HCT116 SW48). Methods: This study was conducted in National Institute of Genetic Engineering and Biotechnology (NIGEB) (Tehran, Iran) from 2017 to 2019. The cytotoxicity of this essential oil was assessed by 3- (4,5-di-methylthiazol-2-yl)- 2,5-diphenyltetra-zolium bromide (MTT) assay, trypan blue exclusion, and colony formation assays. We assessed apoptosis and measure intracellular reactive oxygen species (ROS) by flow cytometry. Then gene expression was analyzed by Quantitative Real-Time RT-PCR. Results: Z. multiflora Boiss., essential oil time- and dose-dependently inhibits cell proliferation and also induced apoptosis in both cell lines via UCP2-related mitochondrial pathway by the induction of intracellular ROS. Conclusion: Z. multiflora Boiss., essential oil could be a good candidate for use as an inhibitor of the growth of colorectal tumor cells.