#1 Calciopoli (Serie A)
Italian football in 2006 was rocked to its core. Off the back of Italy's World Cup win, it was found that some of the biggest clubs in the country, including Juventus, Fiorentina, Lazio, and AC Milan, had been involved in the practice of affecting the selection of officials for their matches for advantage.
The scandal was not taken lightly, as the major culprits, Juventus, were relegated to the second division, given a points deduction, and stripped of their 2005 and 2006 Serie A titles.
The club's director, Luciano Moggi, was banned from football and given a 5 year prison sentence. The other clubs and their directors suffered similar but lesser punishments. Italian football has only now fully recovered from the Calciopoli scandal, with Juventus back on top of Serie A.
These are the most infamous and well documented match fixing scandals in recent history, let me know in the comments if I have missed any!