It included 18 events, starting at Losail in Qatar on 28 February, and ending at San Bernardino, California in the United States on 20 September.
[1] In the main MXGP class, Tony Cairoli was the six-time defending champion, and entered the 2015 season looking to score a record seventh consecutive premier class title, for Red Bull KTM.
Nagl got injured on practice and missed the next 5 rounds, ending his hopes of a maiden championship.
In the MX2 class, Jordi Tixier was the defending champion, after taking the title in the final race of the 2014 season, also for Red Bull KTM.
[1] In February 2015, it was announced that the Brazilian event – scheduled to be held on 16 August in Trindade – had been cancelled due to financial and political issues.