We have elucidated the cytoprotective effect of annphenone (2,4-dihyroxy-6-methoxy-acetophenone 4-O-beta-D-glucopyranoside) against oxidative stress-induced apoptosis. Annphenone scavenged intracellular reactive oxygen species (ROS) and increased antioxidant enzyme activities. It thereby prevented lipid peroxidation and DNA damage, which was demonstrated by the inhibition of the formation of thiobarbituric acid reactive substance (TBARS), inhibition of the comet tail and decreased phospho-H2A.X expression. Annphenone protected Chinese hamster lung fibroblast (V79-4) cells from cell death via the inhibition of apoptosis induced by hydrogen peroxide (H2O2), as shown by decreased apoptotic nuclear fragmentation, decreased sub-G1 cell population and inhibited mitochondrial membrane potential (Deltapsi) loss. Taken together, these findings suggest that annphenone exhibits antioxidant properties by inhibiting ROS generation and thus protecting cells from H2O2-induced cell damage.