Vessel endothelium injury caused by reactive oxygen species (ROS) including H(2)O(2) plays a critical role in the pathogenesis of cardiovascular disorders. Therefore, agents or antioxidants that can inhibit production of ROS has highly clinical values in cardiovascular therapy. Curculigoside is the major bioactive compounds present in Curculigo orchioides, and possess potent antioxidant properties against oxidative stress insults through undefined mechanism(s). The present study was designed to test the hypothesis that curculigoside can inhibit H(2)O(2)-induced injury in human umbilical vein endothelial cells.