This article details the qualifying phase for sailing at the 2020 Summer Olympics (postponed to 2021^[2] due to the COVID-19 pandemic). 350 quota places for the Games are entitled to the sailors coming from their respective NOCs, based on the results at designated regattas supervised by World Sailing. Host nation Japan has been guaranteed one quota place in each of the ten classes.

This section tabulates the heads of qualification in a form suitable to be filled in as events progress. The full qualification rules[1] for sailing published by WS contain intricate conditions too lengthy for inclusion in Wikipedia.

The qualification period commences at the 2018 Sailing World Championships in Aarhus, Denmark, where about forty percent of the total quota will be awarded to the highest finishing NOCs. Six places will be available in the men's Laser and women's Laser Radial classes at the 2018 Asian Games and 2019 Pan American Games, whereas sixty-one more will be distributed to the sailors at the World Championships for all boats in 2019. Moving towards 2021 because of the consequent Olympic postponement and the COVID-19 pandemic, continental qualification regattas will be held to decide the remainder of the total quota, while two spots each in the one-person dinghy classes will be granted to eligible NOCs through the Tripartite Commission Invitation.^[3][1]