The number could increase, pending wildcard entries for athletics and changes to the tennis draw, the Brazilian Olympic Committee said on Monday, reports Xinhua.
The squad includes 253 men and 209 women, in addition to 344 coaches, medical staff and team officials.
Previously, the largest Brazilian squad at the Olympics was 277 at the Beijing Games in 2008. At the 2012 London Olympics, Brazil fielded 259 sportspersons.
Track and field will have the largest number of Brazilian competitors at 67, followed by football (36) and swimming (33).
Members of the host nation's squad will begin arriving at the athletes' village next Sunday (June 24).
Women's hockey is the only event in which Brazil will not field a team, due to the country's inability to meet minimum criteria for the sport.