The triathlon competitions at the 2020 Summer Olympics in Tokyo featured fifty-five athletes competing in each of the men's and women's events.

Qualification places are awarded first through the ITU mixed relay rankings of 31 March 2020, with seven NOCs each earning four quota spots (two per gender).

Three more NOCs can earn four quota spots apiece at the 2020 ITU Mixed Relay Olympic Qualification Event.

Individual rankings of 11 May 2020 are considered next, with the top 26 individuals per gender qualifying, subject to the limit of three per NOC and ignoring the first two from each NOC that qualified via mixed teams.

The final two spots per gender are awarded through Tripartite Commission invitations.