The Irish forward started his career playing for Adamstown and his county, Wexford, before moving to his first professional club St Patrick's Athletic in September 2001. Doyle initially played for the club's under 18 side but within months had made his League of Ireland debut. He then had a successful spell with Cork City which he joined in February 2003. Doyle scored 25 goals for Cork City where he began playing on the right-wing but soon reverted to his natural position of striker.

On 7 June 2005, Doyle signed for Reading from Cork City for €117,000 (about £78,000). Despite having left Cork City, Doyle received a championship medal when they won the Eircom League Premier Division in November 2005. Originally, he was signed as a back-up, but injuries to other players elevated him to the first team where his natural goalscoring ability and defence-splitting speed resulted in a goal-scoring spree. He became an intrinsic part of Reading's Championship-winning 2005-06 squad, and according to the Actim Index was one of the top players in the Championship. In April 2006, he was named as Championship Fans' Player Of The Year and one of the Championship Team of the Year by the Professional Footballers' Association.

Doyle is currently playing an important role for Reading in their 2006-07 Premiership season. His first Premiership goal came in The Royals' 2-1 defeat at Aston Villa, Doyle heading Reading in to a third minute lead. On 16 September 2006, he went one better and scored one of the fastest goals in Premiership history, hitting the net just sixteen seconds into Reading's clash with Sheffield United at Bramall Lane, even though it was the home side that kicked-off. Perhaps the highlight of Doyle's Premiership season so far came against Manchester United, the side the striker supported as a boy. After Gary Neville handballed in the box, Doyle smashed the penalty past goalkeeper Edwin van der Sar to put Reading in front. The Royals drew the game 1-1.

Doyle has played for the Republic of Ireland U21 team, debuting on 2 February 2004 against Portugal. With 11 caps, and scoring 5 goals, he was also a member of the Irish FIFA World Youth Championship squad in 2003. He was called up to the Irish international squad in October 2005, making his international debut against Sweden at Lansdowne Road on 1 March 2006. His first start in an competitive international against Germany on 2 September 2006 in a 2008 UEFA European Football Championship qualifier. With this appearance, his family also won a €100 bet at 100/1 they had placed two years on Doyle playing competitively for Ireland. Doyle scored his first goal for Ireland against San Marino in November 2006.

--Wikipedia