Kristian 'Kris' Denis O'Leary (born 30 August 1977) is a Welsh football coach and former professional footballer. He is best known for his spell's both as a player and coach at Swansea City. He formerly managed Welsh side Neath between 2011 and 2012.
Born in Port Talbot, O'Leary began his career as a trainee at Swansea City, having signed for the club as a schoolboy at the age of 14 in 1992. He made his professional debut for the club during the 1995–96 season. His favoured position is in midfield, although he has also played in central defence and at right-back. O'Leary spent part of the 2002–03 season as the club captain, but the team met with little success and he gave up the role.
O'Leary was a one club man until November 2006 when he joined Cheltenham Town on a month's loan, later turning down the chance to move to the club on a permanent basis. In August 2009, he moved to Leyton Orient on a one-month loan deal, making three appearances before returning to Swansea. Having made over 300 appearances for Swansea City in a spell lasting nearly 15 years, O'Leary left the club by mutual consent on 2 February 2010. After a spell training with Hereford United, on 17 March he turned out as a trialist for Wrexham reserves against Preston North End reserves after training with the Conference side the week before. On 26 March 2010 he signed an initial one-month contract with the club with a view to a longer deal, making his debut the following day in a 3–0 win over Histon.
On 12 July 2010, he joined Welsh Premier League side Neath. The club stated that "Kris is invaluable to add steel and direction to a young squad in readiness for next season".
On 15 November 2011, he was named caretaker manager after the departures of Neath's management team. He left the club at the end of the season following the club's liquidation.
On 5 July 2012, he rejoined Swansea City, this time as a youth team coach. His job at Swansea would involve coaching the young professionals as manager of the reserve team. In 2015 he moved positions within the club to start working with the first team and he was made assistant first team coach.
On 9 December 2015, O'Leary left his position at Swansea City, along with Pep Clotet and James Beattie, following the sacking of manager Garry Monk.