Prostate cancer (PC) is one of the most commonly diagnosed cancer types being the second major reason of cancer-associated death in male particularly over the age of 50. Accumulating scientific evidences suggest the role oxidative stress and reactive oxygen species (ROS) in prostate cancer. A variety of factors including carcinogenic molecules, infectious diseases and toxic compounds can induce ROS production which turns into a strong contribution to the disturbed homeostasis and genetic mutation. Antioxidants can decrease the negative effects of ROS in vitro. Vitamin C (Ascorbic acid, Asc), vitamin A (beta carotenoids and retinoids, β-Crt) and vitamin E (alpha tocopherol, α-Toc) play an important role in inhibition of oxidative stress and diminishing of free radicals in the body. The aim of this study was to determine the anticancer effect of α-Toc, β-Crt and Asc on PC-3 prostate cancer cells in vitro. This was carried out by cell proliferation, ROS and Lipid Peroxidation assay, caspase-3 and propidium iodide staining experiments. The findings suggest that these agents behave as prooxidant by lowering cell viability and increasing the production of ROS and LPO in prostate cancer. These oxidants induce apoptosis as supported by caspase-3 (the enzyme playing key role in programmed cell death) staining by displaying a marked increase in the expression level of caspase-3 enzyme.