Andrew David Morton (born 1953) is an English journalist and writer who has published biographies of royal figures such as Diana, Princess of Wales, and celebrity subjects including Tom Cruise, Madonna, Angelina Jolie and Monica Lewinsky; several of his books have been unauthorised and contain contested assertions.

Andrew David Morton was born and raised in Halton, Leeds, West Riding of Yorkshire, His father ran a picture framing business. He attended Temple Moor Boys' Grammar School, Leeds and Sussex University where he studied history. After university, Morton became a tabloid journalist and worked for three London tabloids, the Daily Star, News of the World, and Daily Mail, until 1987.

Andrew Morton wrote a biography of Diana, Princess of Wales called Diana: Her True Story. Unable to interview Diana in person, he passed along interview questions through her friend James Colthurst. In 1993 it was made into a television film of the same name, with Serena Scott Thomas as Diana. Following Diana's death in August 1997, Morton issued an edition entitled Diana: Her True Story in Her Own Words in October and acknowledged Diana's role as the book's main source of information. The revelation, which came after years of denial of getting any input from Diana for the book, together with the release of her recorded conversations on tapes caused a mixed reaction in the press, with some accusing Morton of breaching confidentiality and exploiting the tragedy of her untimely death and others praising his candour.

On 16 November 2010, Prince William announced his engagement to Catherine Middleton. Morton was commissioned by Michael O'Mara Books to write a book to coincide with the royal wedding on 29 April 2011. The book, which went on sale on 3 May 2011 in the UK, includes a detailed biography of Prince William, as well as details of his relationship with Catherine Middleton. The book features full-colour photos of Prince William and the couple, as well as a detailed section on the wedding itself.

In April 2018, he published Meghan: A Hollywood Princess about Meghan Markle, who married Prince Harry a month later in May 2018.

His biography of Elizabeth II, called The Queen: Her Life, was published in November 2022, two months after her death. Reviewers commented on the lack of depth, the frequent drawing on information from Morton's previous royal biographies, and the way the book had apparently been rushed through the process of publication.

Tom Cruise: An Unauthorized Biography was published in January 2008, and reprinted with an update in February 2009. In a review in The New York Times, Janet Maslin writes "Mr. Morton has found a number of former Scientologists who are willing to speak freely, and in some cases vengefully, about the group's purported inner workings. Mr. Morton's eagerness to include their voices leads him to push the limits of responsible reporting." Maslin adds that Morton "provides a credible portrait extrapolated from the actor's on-the-record remarks and highly visible public behaviour."

Writing in Entertainment Weekly, Mark Harris gives the book a grade of "C−", and says "Cruise emerges from Morton's takedown moderately scratched but as uncracked as ever." Another review in The New York Times by Ada Calhooun stated: