The athletes will vie in seven sports, namely badminton, swimming, weightlifting, archery, athletics, rowing and cycling, said Lukman Niode, deputy chief of Satlak Prima task force which is in charge of the athletes selection, reports Efe.
"Now we have to resume the tradition of having gold medals in Olympics," he said in a statement.
Twenty five out of the 28 athletes have passed qualification for the Olympics and the rest take wild cards for the Rio Games, Niode said.
In 2012, Indonesia sent 22 athletes to the London Olympics with 19 of them passing qualifications and the rest with wild cards.
Badminton and weightlifting have contributed the most to Indonesia's gold medals in the past Olympics. Indonesia earned gold medals since the 1992 Olympics in badminton, but they failed to get one in the 2012 London Games.
Indonesia bagged a silver and bronze medal each with Weightlifters Eko Yuli Irawan and Triyatno managing to repeat their Olympic medals from the Beijing Games.