Andrew O'Hagan (born 1968) is a Scottish novelist and non-fiction author. Three of his novels have been nominated for the Booker Prize and he has won several awards, including the Los Angeles Times Book Prize.

His most recent novel as of 2024^[update] is Caledonian Road (2024) published by Faber & Faber. His previous novel Mayflies (2020) won the Christopher Isherwood Prize, and was adapted into a two-part BBC television drama of the same name. O'Hagan was executive producer of the TV adaptation.

Andrew O'Hagan was born in Glasgow in 1968, of Irish Catholic descent, and grew up in Kilwinning, North Ayrshire. His mother was a school cleaner, his father worked as a joiner in Paisley, and he had four elder brothers. His father was a violent alcoholic, and as a boy, he would hide books from his father under his bed.

He attended St Winning's Primary, then St Michael's Academy, before studying at the University of Strathclyde, the first in his family to reach tertiary education. He earned his BA (Honours) in English in 1990.

In 1991, O'Hagan joined the staff of the London Review of Books, where he worked for four years.

In 1995, he published his first book, The Missing, which drew from his own childhood and explored the lives of people who have gone missing in Britain and the families left behind. The Missing was shortlisted for three literary awards: the Esquire Award, the Saltire Society Scottish First Book of the Year Award, and the McVities Prize for Scottish Writer of the Year award.

In 1999, O'Hagan's debut novel, Our Fathers was nominated for several awards, including the Booker Prize, the Whitbread First Novel Award and the International Dublin Literary Award. It won the Winifred Holtby Memorial Prize.

In 2003, his next novel Personality, which features a character similar to Lena Zavaroni, won the James Tait Black Memorial Prize for fiction. That same year, O'Hagan won the E. M. Forster Award from the American Academy of Arts and Letters.