Henri Jean Pascal Gastaut (April 1915, Monaco – July 1995) was a French neurologist.
He was educated in neurology and neuroanatomy at the University of Marseille, obtaining his medical doctorate in 1945. In 1953 he became head of the neurobiological laboratories at the Marseille Hospital. He was named professor of anatomical pathology in 1954 and director of the regional centre for epileptic children in 1960. In 1973 a chair of clinical neurophysiology was created for him, a tenure he held until his retirement in 1984.
His major interests involved research of electroencephalography and brain functionality in epilepsy. For several years he was secretary general (1957–1969) of the International League Against Epilepsy, where from 1969 to 1973, he served as its president. In 1967 he was elected dean of the University of Marseille School of Medicine.
He attempted to understand possible ties between epilepsy and artistic genius in individuals such as Fedor Dostoyevski, Gustave Flaubert, and Vincent van Gogh, and published a number of papers about this relationship.