"Paris Saint-Germain are very pleased to announce that Thiago Silva has extended his contract by one additional year, keeping him at the club until June 2018," the Ligue 1 champions announced.
"We are very proud to extend Thiago, an exceptional player on and off the pitch," club president Nasser Al-Khelaifi added.
"He symbolises PSG's transition to one of the biggest clubs in Europe."
It is the second major contract news of the week for PSG, with Italy playmaker Marco Verratti agreeing improved terms on his contract on Wednesday.
Silva, 28, has only been at the big-spending French champions for one season but had already been linked with a move to Barca.
Rising to prominence at AC Milan, he joined PSG in a £35 million move that also saw Zlatan Ibrahimovic move to Paris.
Silva has been capped 31 times by Brazil since making his debut in 2008.