Justin O'Neill (born 4 April 1991) is an Australian former professional rugby league footballer who played for the Melbourne Storm and North Queensland Cowboys in the NRL and Australia at international level.

He represented the NRL All Stars and Queensland in the State of Origin series and won premierships with the Storm in 2012 and the Cowboys in 2015.

[5] In November 2008, O'Neill played for the Australian Institute of Sport rugby league team that toured France and the United Kingdom.

[20] O'Neill made his club debut for the Cowboys in round 1 of the 2015 NRL season against the Sydney Roosters, scoring a try.

[citation needed] On 21 February 2016, he was a member of the Cowboys' 2016 World Club Challenge winning side against the Leeds Rhinos at Headingley Stadium.

O'Neill retained his spot at Centre in the Round 3 victory against New Zealand where he ran for a game high 203 metres.

[citation needed] O'Neill was named at centre for the Queensland Maroons in Game I of the 2017 State of Origin Series.

On 1 October, O'Neill started at centre in the Cowboys' 2017 NRL Grand Final loss to his former club, the Melbourne Storm.

[27] In 2019, after being dropped to the Townsville Blackhawks earlier in the season, O'Neill returned to first grade in great try scoring form, with eight tries in eight games.

[29] The following morning he was rushed to hospital where it was discovered that two broken ribs had punctured his spleen, causing internal bleeding.

[30] In 2020, O'Neill successfully returned from his spleen injury, starting at centre in the Cowboys' Round 1 loss to the Brisbane Broncos.