"We spoke during the week and he has decided to retire," Vasco da Gama president Roberto Dinamite told reporters on Thursday.
Juninho, who celebrated his 39th birthday on Thursday, played 393 times for Vasco in three different spells.
He won league championships in 1997 and 2000, a Copa Libertadores in 1998 and a Copa Mercosul in 2000. He scored 76 goals for the Rio club.
Juninho also had a hugely successful career in France with Olympique Lyon, winning the Ligue 1 title seven years in a row between 2002-08.
He also represented Brazil at the 2006 World Cup and helped them lift the Confederations Cup the year before.
Juninho was best known for his incredible free kicks and could hit the ball with pace and accuracy from any angle or distance.
(Writing by Andrew Downie; editing by Tony Jimenez)
