Dennis J. Selkoe (born 25 September 1943) is an American physician (neurologist) known for his research into the molecular basis of Alzheimer's disease. In 1985 he became Co-Director of the Center for Neurological Diseases and from 1990, Vincent and Stella Coates Professor of Neurological Diseases at Harvard Medical School. He is also a Fellow of the AAAS and a member of the National Academy of Medicine.