This book aims to provide a comprehensive review of the most up-to-date knowledge of the sources and molecular mechanisms of oxidative stress, and its role in disease and cancer. It also focuses on the novel agents and methods that can be employed to prevent oxidative stress and associated diseases.The authors first review the most recent data on the basic mechanisms of oxidative stress. The second section discusses oxidative stress leading to several diseases and cancers, and in the third section, the strategies employed in the prevention and treatment of oxidative stress-related diseases are discussed.