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Twelve teams qualified for men's rugby sevens at the 2020 Summer Olympics (postponed to 2021 due to the COVID-19 pandemic). Japan automatically qualified as host, with the top four teams of the 2018–19 World Rugby Sevens Series securing their spots. Afterwards, qualification was determined with each of the six continental confederations determining a representative, and the remaining qualification spot determined through an international sevens tournament.
Great Britain qualified for the Olympics through England's performance as England were the designated home nation that could earn Olympic qualification for Great Britain
^ By agreement between the three unions on the island of Great Britain (England, Scotland, Wales), England, as highest finisher among those nations in the 2017–18 series, represented Great Britain in qualifying for the 2020 Olympic Sevens. The final make-up of the Great Britain men's team was determined by the British Olympic Association.
Rugby Africa held the 2019 Africa Men's Sevens on 9–10 November 2019 in Johannesburg, South Africa, with 2018 regional tournaments serving as a qualifier for the final tournament. Title winners Kenya gained direct entry to the Olympic Games, while Uganda and Zimbabwe progressed to the final qualifying stage. South Africa had already qualified through a top 4 finish in the World Rugby Sevens Series.
England won the tournament, meaning that Great Britain qualified for the 2020 Olympics. The second and third placed teams, France and Ireland, qualified for the inter-continental tournament for the last available slot.
Rugby Americas North held the 2019 RAN Sevens on 6–7 July 2019 at George Town, Cayman Islands. Canada won the tournament and gained direct entry to the Olympics. The second and third placed teams, Jamaica and Mexico, progressed to the final qualifying stage to play for the last available slot. The United States qualified through a top 4 finish in the World Rugby Sevens Series.
Oceania Rugby held the 2019 Oceania Sevens Championship on 7–9 November 2019 at Suva, Fiji. The tournament included Japan as an invited team. Australia won the Oceania title and gained direct entry to the Olympics. As the next highest placing eligible teams not already qualified, Samoa and Tonga progressed to the final qualifying stage to play for the last available slot. Fiji and New Zealand had previously qualified through a top 4 finish in the World Rugby Sevens Series.
Sudamérica Rugby held a tournament on 29–30 June 2019 in Santiago, Chile. The tournament winners Argentina gained direct entry to the Olympic Games, while Brazil and Chile progressed to the final qualifying stage.
A 12-team repechage tournament was scheduled to be held from 20 to 21 June 2020, but was postponed due to the COVID-19 pandemic. Two runners-up from each of the six continental qualification tournaments played, with the winner — Ireland — advancing to the Olympic tournament.