Abstract: In this study, apoptotic mechanism of resveratrol against human prostatic carcinoma DU145 cells was investigated. MTT was used to measure cell growth and proliferation. Reactive oxygen species(ROS)kit was used to analyze ROS level. Cell apoptosis and cell cycle analysis were observed by flow cytometry. Protein expression levels of apoptosis and pathway associated were analyzed by Western blot. The result shows that DU145 cells treated with different resveratrol concentrations suffered apoptosis, cycle arrest in G₀/G₁ phase, ROS increase in the cell and a decrease in mitochondrial membrane potential(MMP, ΔΨ_m), in a concentration-dependent manner. Resveratrol inhibited the expression of Bcl-2 protein via up-regulating Bax protein, thus increasing the ratio of Bax/Bcl-2, activating Caspase reaction and led apoptosis ultimately. Further investigation confirmed that resveratrol increased ROS level, decreased MMP and consequently induced apoptosis via michondrial-mediated pathway in DU145 cells. Therefore resveratrol may induce apoptosis via ROS-michondrial pathway in DU145 cells.