Eugene O'Neill may refer to:

• Eugene O'Neill (1888–1953), American playwright
  • Eugene O'Neill Theatre, Broadway theater
  • Eugene O'Neill Theater Center, Connecticut theater
  • Eugene O'Neill Award, Swedish acting award
  • Eugene O'Neill National Historic Site, Danville, California
• Eugene O'Neill, Jr. (1910–1950), professor of Greek literature, son of the playwright
• Eugene O'Neill (hurler) (born 1978), Irish hurler
• Eugene M. O'Neill (1850–1926), Irish-born American lawyer and newspaper owner

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