The highly-rated defender has been associated with a move to Europe, but he reinforced his stance that he is not yet thinking about a new challenge by signing a new deal
The defender, 24, has long been linked with a transfer to Europe, with AC Milan and Juventus believed to be amongst his main suitors.
However, he has always maintained that he is not yet interested in leaving his homeland of Brazil, and he has now committed his future to the Rio de Janeiro-based club.
"I am very happy at Vasco and it is a great joy to be able to sign an extension," Dede told Vasco's official website.
"Now I have to repay their faith in me on the pitch and help the club win more titles. If God has his way, you will see me here for a long time.
"I would like to make it clear that financial matters were not key for me to stay. There were good offers but, as in everything in life, if it has to happen, it will happen at the right time."
According to Lancenet, Dede's buy-out clause is now set at €28 million. Since arriving at the club in 2009, the two-cap Brazilian has scored 15 goals in 127 matches for Vasco.