Dan Abnett (born 12 October 1965) is a British comic book writer and novelist. He is a frequent collaborator with fellow writer Andy Lanning, and is known for his work on books for both Marvel Comics, and their UK imprint, Marvel UK, since the 1990s, including 2000 AD. He has also contributed to DC Comics titles, and his Warhammer Fantasy and Warhammer 40,000 novels and graphic novels for Games Workshop's Black Library now run to several dozen titles and have sold over 1,150,000 copies as of May 2008. In 2009 he released his first original fiction novels through Angry Robot books.

Abnett graduated from St Edmund Hall, Oxford in 1984.

As one of the more prolific 2000 AD writers, Abnett was responsible for the creation of one of the comic's better known, and longest-running, strips of the last decade, Sinister Dexter. Other original stories include Black Light, Badlands, Atavar, Downlode Tales, Sancho Panzer, Roadkill and Wardog, based on the game of the same name. Abnett has also contributed to some of the comic's major ongoing series, including Judge Dredd, Durham Red and Rogue Trooper.