The 50km World Championships is an annual 50 km ultra-running competition organized by the International Ultramaraton Association (IAU). The competition started as the 50-kilometer IAU World Trophy in 2005. The competition was the final point of the 50 km Challenge IAU circuit, the runners gaining qualifications through the performances registered in one of the nine qualifying races. The winners were determined by the best aggregate time of the World Trophy race plus the best time in the qualifying round. The race departed from this format, and the World Trophy was later decided in a single race, this format continuing until 2014.
The first edition of the 50 km World Championships, as we know it today, took place in Doha, Qatar in December 2015. The last three editions were hosted by Doha, Qatar, because in 2014 a protocol was signed of collaboration by which Doha demonstrated its commitment to high performance.