Nigerian-born Daniel Shittu played for the Under 19s against Derby in a 3-2 FA Premier Academy League defeat. On November 13th 1999, he returned to Carrow Road as part of the Charlton Under 19 side that defeated the young Canaries 2-0.

The former Carshalton Athletic player joined Third Division Blackpool on loan on 16th February 2001 so he could gain match experience including a goal on his debut. On 23rd March 2001, Danny received a surprise international call-up for Nigeria for their April 7th friendly against Libya. However Danny rejected the invite preferring to gain further experience in Division 3 against the likes of Shrewsbury. Blackpool manager Steve McMahon stated in June 2001 that he would be keen to sign Danny permanently to aid the Tangerines in their 2001/02 Division Two campaign.

Danny joined QPR on loan towards the end of October 2001 but was sent-off on his debut. Despite a second sending off. Danny joined QPR permanently in January 2002 for a fee of approximately £250,000. He made his international debut for Nigeria at Loftus Road in their April 2002 clash with Paraguay, and hopes to attend the World Cup in Japan/Korea.

According to speculation recorded on the Football Transfers website, Aston Villa have allegedly been watching Danny during November/December 2002 and are preparing a swoop for him and colleague Clarke Carlisle. Football Rumours have claimed that Southampton have been watching the young Nigerian defender.

QPR won promotion into Division One at the end of the 2003/4 season. After a strong season in 2004/5, Danny was linked with £1.5million moves to Man City or Southampton, and a £2.5million switch to Celtic. He was later linked with a return to the Valley. In December 2005, he was linked with a move to Goodison Park to resolve Everton's defensve frailities. The League Paper speculated on 1st January 2006 that Sheffield United had scouted Shittu and were seeking to sign him to strengthen their push for promotion to the Premiership. On 29th January, The League Paper linked him with moves to Norwich and Birmingham whilst The People speculated that he was to join Charlton for £700,000. The former report suggested that QPR wanted £3million for him.

In March 2006, football magazine Four Four Two listed Shittu as their 20th best player performing in the Football League.

Despite interest from West Bromwich Albion and a £1.5million bid from Baggies manager Bryan Robson, Danny signed for Ade Boothroyd's Watford on 6th August 2006 in a £1.6million deal that could rise to £3m. In November 2006, the Scottish Sun suggested that Shittu was a target for Gordon Strachan's Celtic. Rumours circulated in February 2007 that if Sheffield United avoided relegation from the Premiership, Blades' boss Neil Warnock would make a £3.5m swoop for Shittu.

Shittu was called up for Nigeria's team for the 2008 African Cup of Nations. Whilst away, media speculation linked him with a move to Newcastle United. Danny played in all 4 of Nigeria's games in the African Cup of Nations althoiugh generaly it is thought that the Nigerian side were disappointing.

On 6th August 2008, Danny signed for Gary Megson's Bolton Wanderers for an undisclosed sum even though there had been speculation linking him with a move to Rangers for £1.5m which broke down over personal terms. Shittu signed an initial three-year deal and becomes Megson's fourth signing of the summer

Danny was included in Nigeria's World Cup squad for the finals in South Africa in June/July 2010 and played in all three disappoiing games for the Super Eagles

Danny was released from his Bolton contract on 2nd September 2010 after failing to make it into Bolton's 25 man Premier League squad for the 2010/11 season

He signed for Millwall on 20th October 2010 on a three month contract. Whilst Millwall sought to extend the contract in January, QPR manager Neil Warnock was keen to sign him for his promotion chasing Rangers. Cardiff were also linked. He finally signed for QPR on 27th January 2011

He was released by QPR at the end of the 2011/12 season, having made just one appearance in that campaign.

Shittu rejoined Millwall on 13th August 2012, signing a one year deal.

Shittu was one of eighteen players released by Millwall on 7th May 2015 following their relegation to League One.