Matthew Stephen Dunn (born 2 September 1973) is an Australian former freestyle and medley swimmer who competed in three consecutive Summer Olympics, starting in 1992.

Dunn trained at the Australian Institute of Sport under Russian swimming coach Gennadi Touretski, who also taught Alexander Popov. Dunn was a specialist in the short course (25 m) events, and won several medals in the event in the 1990s. He was a multiple Commonwealth Games gold medallist in the medley events and set a world record in the 4 × 200 m freestyle relay at the 1998 Commonwealth Games in Kuala Lumpur alongside Ian Thorpe, Michael Klim and Daniel Kowalski.

• List of Commonwealth Games medallists in swimming (men)
• List of Commonwealth Games records in swimming
• World record progression 400 metres individual medley
• World record progression 4 × 200 metres freestyle relay

• Matt Dunn at Olympics at Sports-Reference.com (archived)