Haddo is another name for pink salmon. It may also refer to:
, two US Navy submarines Haddo, a community in South Dundas, Ontario, Canada Haddo Peak, Alberta, Canada Earl of Haddo, a subsidiary title of the Marquess of Aberdeen and Temair Oliver Haddo, a character (a caricature of Aleister Crowley) in the 1908 novel The Magician by W. Somerset Maugham Oliver Haddo, a pen name used by Aleister Crowley for a critique of the novel, as well as other writings
See also Haddo House, a Scottish stately home near Tarves in Aberdeenshire