The men's 20 kilometres walk event at the 2020 Summer Olympics took place on 5 August 2021 in Sapporo.

[1] Approximately 60 athletes competed; the exact number was dependent on how many nations use universality places to enter athletes in addition to the number qualifying through time (no universality places were used in 2016).

Due to the COVID-19 pandemic, the period was suspended from 6 April 2020 to 30 November 2020, with the end date extended to 29 June 2021.

[2][4] In July 2020, World Athletics announced that the suspension period would be lifted for the road events (marathons and race walks) on 1 September 2020.

[8] Prior to this competition, the existing world, Olympic, and area records were as follows.