John Duggan

John Duggan may refer to:


 * John Duggan (rugby, born 1929) (1929–2022), English former rugby union and rugby league footballer
 * John Duggan (rugby union, born 1948), Irish former Leicester Tigers winger
 * John Duggan (bishop) (1918–2000), Bishop of Tuam, Killala, and Achonry, 1970–1985
 * Jack Duggan (politician) (1910–1993), Australian politician for Electoral district of Toowoomba West
 * Johnny Duggan (jockey), on racehorse Gold and Black
 * John Duggan, main character in the TV series Duggan
 * John Duggan, character in the TV series The Thick of It
 * Jack Duggan (ice hockey) (1897–1977), ice hockey player
 * Jack Duggan (politician) (1910–1993), member of the Queensland Legislative Assembly
 * John Duggan (political scientist) of the Duggan–Schwartz theorem