Sickle cell disease is a blood disorder that affects erythrocytes one of the most common single gene disorders in the world and the incidence is high in Turkey. Mutation in the beta globin gene leads to the formation of sickle hemoglobin tetramers. These tetramers polymerize and damage the erythrocyte membrane. Erythrocyte damage; It creates a vicious circle by triggering pathophysiological mechanisms such as hemolysis, vaso-occlusion, endothelial dysfunction and inflammation. These mechanisms cause varying degrees on each patient chronic hemolytic anemia, vasculopathy, acute and / or chronic organ damage and shortened lifespan. This review provides a comprehensive overview of the molecular and cellular pathophysiology of sickle cell anemia.