Aging is a major risk factor for neurodegenerative diseases such as Alzheimer?s disease (AD). Oxidative stress and free radicals have important biological functions. However, redox imbalance results in oxidative stress that has been implicated in the pathology of many human diseases including AD. The author reviews the involvement of reactive oxygen species (ROS) in the pathogenesis of neurodegenerative diseases, particularly, the interaction of oxidative stress with other critical mechanisms of AD, especially summarized the results about protect effects of tea polyphenols, L-theanine, astaxanthin, EGb761,soy isoflavones and nicotine on AD in cell, animal models and clinical treatments. Hopefully, this review can provide insights into novel preventive and therapeutic strategies for AD.