Peter Arthur Calabresi (born 1962) is an American neuroscientist and neurologist who studies multiple sclerosis. He is Professor of Neurology, Neuroscience, and Ophthalmology at the Johns Hopkins School of Medicine, where he directs the Division of Neuroimmunology and Johns Hopkins Multiple Sclerosis Center. Calabresi was awarded a five-year MS center grant from the National MS Society for the study of mechanisms of neurodegeneration and strategies for neuroprotection in MS.