Conn may refer to:

• Conn (name), a family name and a masculine given name
  • Conn, mythological son of Ler from the Children of Lir legend
  • Conn of the Hundred Battles, a figure from Irish mythology
  • Jerome W. Conn, American endocrinologist
• Connecticut, State in the northeastern United States
  • Connecticut College, a liberal arts college in New London, Connecticut, USA
• Conn, Mississippi, United States
• Conn, Ontario, Canada
• Conn (nautical), the duty of giving directions for movement from the deck of a ship to the helm
• C.G. Conn, Inc., a manufacturer of musical instruments
• CONN (functional connectivity toolbox), a cross-platform imaging software program