Corinthians won South America's elite club trophy for the first time by beating Riquelme's side 2-0 in the second leg of the final in Sao Paulo on Wednesday night, recording a 3-1 aggregate victory.
"I've told the (club) president I'm not going to carry on," former Barcelona and Villarreal playmaker Riquelme told reporters at the Pacaembu.
"I feel empty. I haven't got anything else to give to the club," said the 34-year-old who helped Boca to their 10th final in search of a record-equalling seventh crown.
"I can't play at half (steam)," Riquelme added before saying he would decide soon if he would continue his career at another club.
Former Argentina coach Sergio Batista sounded out Riquelme recently to try to persuade him to join his Chinese team Shanghai Shenhua.
Riquelme had three spells at Boca, the club where is an idol and a fan, after emerging from the youth scheme at first division rivals Argentinos Juniors.
He helped Boca win the Copa Libertadores three times, the old Intercontinental Cup once, the Copa Sudamericana and five Argentine league titles.
"I've lived through a lot these past six months. I didn't expect to play in another Copa Libertadores final," said an emotional Riquelme.
He played at the 2006 World Cup for Argentina, helping them reach the quarter-finals before going out on penalties to hosts Germany, and the Copa America in 1999 and 2007.
Riquelme was an over-age player in the side that won the Olympic gold medal in the 2008 Beijing Games under Batista