Guy Adam Pratt (born 3 January 1962) is a British bassist. He has worked with artists including Pink Floyd, Roxy Music, Gary Moore, Madonna, Peter Cetera, Michael Jackson, the Smiths, Robert Palmer, Echo & the Bunnymen, Tears for Fears, Icehouse, Bananarama, Iggy Pop, Tom Jones, Debbie Harry, Whitesnake, Womack & Womack, Kirsty MacColl, Coverdale•Page, Lemon Jelly, the Orb, All Saints, Stephen Duffy, Robbie Robertson, and A. R. Rahman. In addition to his work as a session musician, Pratt has been a member of the Australian rock band Icehouse, and is currently a member of the band Nick Mason's Saucerful of Secrets with Gary Kemp of Spandau Ballet.

Pratt has also been an actor and worked on TV and film soundtracks, including Dick Tracy (1990), Last Action Hero (1993), Hackers (1995), Still Crazy (1998) and Johnny English Reborn (2011). In 2005 he debuted a one-man music and comedy show.