|Date of birth||14 June 1985|
|Place of birth||Casablanca, Morocco|
|Height||1.78 m (5 ft 10 in)|
|Raja de Casablanca|
|2016||→ Al Ahli (loan)||13||(10)|
|2017–2018||Raja de Casablanca|
|* Senior club appearances and goals counted for the domestic league only and correct as of 6 December 2014.
‡ National team caps and goals correct as of 6 December 2014
In 2013, Iajour became the first African footballer to be FIFA Club World Cup's top scorer and Bronze Ball, advancing with Raja Casablanca into the final played against European champions Bayern Munich. Previously, only Congolese Dioko Kaluyituka won the Silver Ball in 2010.
Iajour began his career at his hometown club Raja Casablanca, in 2003. After staying there for four years, he moved to FC Chiasso. He returned to Raja Casablanca in 2012. After a season, He won his first league title with Raja. In 2013, Raja qualified to FIFA Club World Cup as league champions of host country. On 11 December 2013, Iajour scored a goal in the 2–1 victory against Auckland City, in the play-off for quarter finals. His team eventually defeated Monterrey with 2–1 in the quarter finals to pass in the semi-finals. On 18 December 2013, he scored a goal in the historical 3–1 victory against Atletico Mineiro in the semi-finals. But in the final, Raja Casablanca was defeated by UEFA Champions League holders, Bayern Munich with 2–0. Iajour become one of the FIFA Club World Cup top scorers for 2013, together with Dario Conca, César Delgado and Ronaldinho. He received the FIFA Club World Cup bronze ball.
In August 2007 when the Arabian Clubs Tournament was finished, Mouhcine decided to stay in Switzerland without the permission of his club Raja Casablanca. On 28 October 2007, Iajour has appeared for the first time in official match with the team of FC Chiasso.
In the 2005 FIFA World Youth Championship Iajour has scored three goals and helped Morocco to move to the semi-finals, where they were defeated 3–0 by Nigeria. Morocco ended the tournament in fourth place after a 2–1 loss to Brazil.
In January 2014, coach Hassan Benabicha, invited him to be a part of the Moroccan squad for the 2014 African Nations Championship. He helped the team to top group B after drawing with Burkina Faso and Zimbabwe and defeating Uganda. The team was eliminated from the competition at the quarter final zone after losing to Nigeria.
- Thomas, Durosimi (19 July 2004). "Under-20 round-up". BBC Sport. Retrieved 9 April 2009.
- "Awards for Bayern duo and Iajour". Fédération Internationale de Football Association. Retrieved 21 December 2013.
- "2010 FIFA Club World Cup awards". Fédération Internationale de Football Association. Retrieved 5 March 2013.
- "Morocco name Chan squad". goal.com. Retrieved 12 March 2014.
- "Burkina Faso/Morocco: Chan 2014 - Morocco and Burkina Faso On the Scene, All the Day's Program". allafrica.com. Retrieved 12 March 2014.
- "CHAN 2014: Final Result: Morocco 3 - 1 Uganda". cafonline.com. Retrieved 12 March 2014.
- "CHAN 2014: Morocco, Zimbabwe Clinch Quarter Finals places with Last Group B wins". tripolipost.com. Retrieved 12 March 2014.
- "CHAN 2014: Nigeria stun Morocco to make the semi-final". allsports.com.gh. Retrieved 12 March 2014.