Lagi Setu (born 25 February 1988) is a New Zealand professional rugby league footballer for the Sydney Roosters of the National Rugby League. He primarily plays second-row, prop and lock.
Born in Auckland, New Zealand, Setu played his junior football in Ipswich, Queensland, playing rugby union, before being signed by the St. George Illawarra Dragons. He played for the Dragons' Premier League reserve-grade team in 2006. In Round 2 of the 2007 NRL season he made his NRL debut for the Dragons against the Newcastle Knights. In 2008, Setu played 2 games for the Dragons' Toyota Cup team, scoring 1 try.
On 31 July 2008, Setu signed a contract with the Brisbane Broncos starting in 2009.
In 2010, Setu announced he would be leaving the Broncos to serve a 2-year mission for The Church of Jesus Christ of Latter-day Saints in Birmingham, England starting in 2011.
On 13 September 2012, Setu announced his return from his mission, signing a 1-year contract with the Melbourne Storm starting in 2013. His first game was interchange for Storm's 2013 World Club Challenge win over Leeds.
He has signed with the Canberra Raiders for the 2014 season on a two year deal. Setu didn't make an appearance for the Raiders in the 2014 season.
On 6 November 2014, Setu signed a 1 year deal with the Sydney Roosters for the 2015 season.
In 2008, Setu was named in the Samoan training squad for the 2008 Rugby League World Cup. He made the final squad and played 2 games.