Cancer is one of the most common human chronic diseases worldwide with high mortality rates. It represents the second leading cause of deaths worldwide. Recent advances in the pathogenesis, diagnostics and management of cancer have strongly impacted its primary prevention using therapeutic dietary intervention. In this context, wild plants are rich in bioactive components and, hence possessing therapeutic values. There are many indigenous plant species/varieties grown in Oman which can be used for medicinal purposes because of their bioactive constituents (phenolic and flavonoids compounds). In this research project, we explored the anticancer properties of these plants and their bioactive agents in preventing the oxidative stress-associated carcinogenesis using in vitro human cultured cells. Our results indicate that the assayed Omani indigenous plants have anti-oxidant/free radical scavenging ability by causing growth inhibition and death of two different human cultured cancer cell lines (Hepatic carcinoma (HepG2), Colon cancer Caco 2 cells, and PC3 Prostate cancer cell lines) .