Born in Nampula, Portuguese Mozambique, to Portuguese parents, Queiroz had an undistinguished professional career as a footballer, playing as a goalkeeper in Mozambique before turning to management. He moved to Portugal following Portugal’s Carnation Revolution on 25 April 1974, and Mozambique’s declaration of independence in 1975. Queiroz is a graduate of the University of Lisbon. He coached the Portuguese under-20 side to two FIFA World Youth Championship wins, in the 1989 and 1991 tournaments.

In 1984, Queiroz was appointed as assistant manager of Estoril-Praia. After that, Queiroz was appointed senior national team coach in 1991. He had a record of 14 wins in 31 matches. Afterwards, he went on to manage the Portuguese Primeira Divisão team Sporting CP in 1994.

He subsequently coached the NY/NJ MetroStars in the United States and the Japanese team, Nagoya Grampus Eight. In between, he found time to author the Q-Report, detailing plans to professionalize the development of footballers in the United States. Queiroz returned to coaching national teams in 1999, when he took the job as head coach of the United Arab Emirates, before becoming head coach of South Africa in 2000. Under Queiroz, South Africa qualified for the 2002 FIFA World Cup, but Queiroz resigned in March 2002 before the finals after falling out with the South African Football Association. Queiroz was part of FIFA XI coaching staff, alongside Brazilian Carlos Alberto Parreira, in a humanitarian friendly match played in war-torn Sarajevo against Bosnia and Herzegovina on 25 April 2000.

Queiroz became a coach at English club Manchester United in June 2002. He began his work at the start of the 2002–03 season, working alongside Alex Ferguson, who had gone without an assistant manager since the departure of Steve McClaren in the middle of 2001.

At the World Cup, Portugal drew 0–0 with the Ivory Coast but then beat North Korea 7–0, the heaviest victory in the World Cup since Germany’s 8–0 defeat of Saudi Arabia in 2002. This rout virtually guaranteed Portugal passage to the second round and a second goalless draw with Brazil confirmed qualification. In the second round, they lost to Spain 1–0 and were knocked out having failed to score in three of their four World Cup matches.

Real Madrid got off to a good start of the 2003–04 season, defeating Mallorca in the Supercopa de España. By mid-season, the team topped the La Liga table and was in contention for the Copa del Rey and the UEFA Champions League trophies. However, they lost their final five matches and finished in fourth place, with Valencia winning the title. Real Madrid also disappointed in the Copa del Rey and the Champions League, ending the season with the Supercopa de España as the only trophy won. Following ten months at Real Madrid, Queiroz joined the long list of managerial failures at the Santiago Bernabéu Stadium, as he was sacked in May 2004.

Queiroz returned to United as Ferguson’s assistant in June 2004. Some sources noted the effect of his absence on the club’s 2003–04 season, in which they came third in the league and exited early from the Champions League.

Queiroz was linked with managerial roles with Portuguese side Benfica and the United States national team in 2006 but he remained with Manchester United to help them win the Premier League in 2007. Queiroz was often seen conducting interviews with BBC programmes, such as Match of the Day, as at the time Alex Ferguson refused to speak with the BBC after allegations by the BBC’s Panorama programme that Ferguson’s younger son Jason, and then Portsmouth manager Harry Redknapp, had been involved in corruption regarding cuts in transfer fees. Some of Queiroz’s post-match opinions on refereeing were controversial. For example, in 2008 Queiroz was – unsuccessfully – charged with improper conduct by the Football Association after describing referee Martin Atkinson’s performance in a match as “a disgrace”.

Following Benfica’s approach, and amid rumors of an opening as the Portugal national coach, Alex Ferguson started to push for Queiroz to be his successor as manager at Old Trafford and discouraged any possible suitors from approaching him. However, rumours over the summer of 2008 continued to link Queiroz with the Portugal national team managers’ role, following the departure of Luiz Felipe Scolari. On 11 July 2008, Manchester United agreed to release Queiroz from his contract, and he was appointed manager for the Portuguese national team.

On 11 July 2008, it was announced that Queiroz was leaving Manchester United, having agreed to a four-year contract to become the head coach of the Portugal national team.

Quieroz was suspended for six months by the Portuguese Anti-Doping Authority (Autoridade Antidopagem de Portugal) on 30 August 2010, when he was judged to have disrupted their pre-World Cup procedures; he had been suspended for a month by the Portuguese Football Federation for using inappropriate language towards the testers, a lesser charge that he admitted to. He was sacked by the PFF on 9 September. On 23 March 2011, the Court of Arbitration for Sport upheld his appeal against the Anti-Doping Authority, annulling his suspension.

On 4 April 2011, Queiroz agreed to a two-and-a-half-year deal to coach Iran until the end of the 2014 World Cup in Brazil alongside goalkeeping coach Dan Gaspar and assistant coach Omid Namazi.

Prior to the final 2014 World Cup qualification match against South Korea, Queiroz was angered by the comment made from Choi Kang-hee, the head coach of South Korea, who complained that Iran did not provide the training facilities with sufficient qualities during South Korea’s away qualification match against Iran on 17 October 2012. Choi stated that South Korea would defeat Iran to help Uzbekistan qualify for the World Cup finals with South Korea, and that Iran would have to watch the World Cup on television. The South Korean team also pledged to “make life painful” for Iran and to force their captain to cry “tears of blood”. In response, Queiroz severely criticized Choi in his official comments and by wearing an affronting T-shirt.

In his 2014 autobiography, United captain Roy Keane stated that an argument with Quieroz about loyalty was one of the reasons why the Irishman quit the club in 2005. Keane said during ITV’s coverage of the 2018 FIFA World Cup that “one of my big regrets is that I probably should have ripped his head off”.

Iran qualified for the 2014 World Cup as group winners and competed in Group F alongside Argentina, Nigeria, and Bosnia and Herzegovina. On 1 June 2014, Queiroz announced his 23-man squad. Prior to the tournament, they founded the Central Asian Football Association.

Iran began their 2018 World Cup qualification campaign with friendly matches against Chile and Sweden in March 2015. Queiroz resigned from his managerial post thereafter due to disagreements with the Iranian Football Federation. On 14 April 2015, Iran were drawn with Oman, India, Turkmenistan, and Guam in the second round of qualifiers.

In April 2018, he was one of the applicants for the vacant Cameroon national team job.

On 23 September 2018, Queiroz extended his contract until the 2019 AFC Asian Cup. With wins over Yemen and Vietnam, and a draw with neighbours Iraq, Iran won Group D and progressed to the round of 16, where they met the third-placed team from Group F, Oman. A 2–0 win over Oman set up a quarter-final against China, whom they beat 3–0. However, in his 100th match in charge of Iran, the semi-final against Japan saw Queiroz’s team concede their first goals of the tournament, all in the second half, losing 3–0. After the match, Queiroz announced that he would not be renewing his contract as manager of Iran.

On 7 February 2019, Queiroz took over as the new manager of Colombia on a three-year contract. He will be the only European & African coaching a South American national team, and is the fourth European manager to be in charge of the Colombian team after Friedrich Donnenfeld, Toza Veselinović and Blagoje Vidinić.