P66shc is a gene that regulates the level of reactive oxygen species (ROS), apoptosis induction, and lifespan in mammals. Mice knocked out for p66shc have a lifespan ~30% longer and demonstrate an enhanced resistance to oxidative stress and age-related pathologies such as hypercholesterolemia, ischemia, and hyperglycemia. In this respect, p66shc is a promising pharmacological target for the treatment of age-related diseases. In this review, an attempt has been made to survey and put to a critical analysis data concerning the involvement of p66shc in the different signaling pathways that regulate oxidative stress and apoptosis.