The New South Wales Under-18's rugby league team, also known as New South Wales Under-18's or New South Wales U18, represents New South Wales in the sport of rugby league at an under-18 age level. Since 2008, the team has played an annual fixture against the Queensland Under-18's team as a curtain raiser to a State of Origin game. The team features players selected from New South Wales's premier under-18 rugby league competition, the S.G. Ball Cup. They are administered by the New South Wales Rugby League.
New South Wales saw success in the first four under-18 Origin fixtures, winning every game until 2012. New South Wales would win another two more fixtures in 2013 and 2014 before picking up their second lose in 2015, losing to Queensland 22-18 at the Melbourne Cricket Ground. Since 2015 New South Wales have won every under-18 Origin fixture, in 2016, 2017 and 2018.