Men's race at the 2021 UCI Mountain Bike Marathon World Championships took place in Elba on 2 October 2021.

The 2021 XCM World Championship was held over a 35km course with 3 laps plus an initial 2km lap and a final 8km lap.

In total, the men's race was 115 km with a difference in altitude of 4,500 metres.

[1][2] 114 competitors from 26 nations started.

[3] 75 competitors reached the finish line.