Fritz Heinrich Lewy (/ˈlɛvi/; January 28, 1885 – October 5, 1950),^[1] known in his later years as Frederic Henry Lewey, was a German-born American neurologist. He is best known for the discovery of Lewy bodies, which are a characteristic indicator of Parkinson's disease and dementia with Lewy bodies.^[2]

Lewy was born to a Jewish family in Berlin, Germany, on January 28, 1885. He trained in Berlin and Zürich and graduated from Berlin^{[clarification needed]} in 1910. He worked in Alois Alzheimer's Munich laboratory and was contemporary with Hans Gerhard Creutzfeldt (1885–1964), Alfons Maria Jakob (1884–1931) and Ugo Cerletti (1877–1963). In 1933, he fled Nazi Germany and moved to the United States.^[3] Lewy died in Haverford, Pennsylvania, on October 5, 1950, aged 65.