Alistair Leslie Graham, better known as Ali G, is a satirical fictional character created and performed by English comedian Sacha Baron Cohen. A faux-streetwise poseur from Staines, England, Ali G speaks in rude boy-style Multicultural London English and brags about coming up "in da heart of da Staines ghetto" and leading a local street gang, "Da West Staines Massiv." He conducts interviews with unsuspecting subjects who do not realise they have been set up.

Ali G first appeared as the "voice of da yoof" on Channel 4's The 11 O'Clock Show in 1998, and he subsequently became the title character of Da Ali G Show in the early 2000s, and was also the title character of the film Ali G Indahouse. In a 2001 poll by Channel 4, Ali G was ranked eighth on their list of the 100 Greatest TV Characters.

In a 2007 interview with The Daily Telegraph, Baron Cohen announced that Ali G, along with Borat (another fictional character made by Baron Cohen), had been retired. However, Ali G returned at the 2012 British Comedy Awards to accept Baron Cohen's Outstanding Achievement Award, causing controversy by making jokes about Kate Middleton and Jimmy Savile. Ali G returned to television with Ali G Rezurection in 2014. Rezurection features new footage of Ali G introducing old highlights of Da Ali G Show, while Borat reappeared for Borat Subsequent Moviefilm in 2020.