De Jong signed for Barcelona from Ajax in a huge transfer of £ 65 million which is the largest of the winter window so far.
The 21-year-old, widely regarded as one of Europe's most promising midfielders, will join the Catalan giants on July 1st.
The transfer of De Jong to Barcelona was confirmed in a brief statement on their official website, with the Laiga giants who said: "FC Barcelona and Ajax have reached an agreement for the transfer of midfielder Frenkie de Jong, who will join the Catalan club from 1 July 2019.
"The cost of the transfer transaction is 75 million euros, in addition to an additional 11 million variables.
"The player will sign a contract for the next five seasons, until 2023/24.
"President Josep Maria Bartomeu and CEO Oscar Grau have been personally involved in concluding the agreement in Amsterdam."
However, Barcelona signing De Jong could be bad news for Manchester United and PSG.
Both clubs would love to sign Ajax Matthijs De Ligt.
De Ligt, like De Jong, is considered one of the most promising assets of European football.
The central defender is sought after at United, with Ed Woodward presumably ready to break the bank to land him.
The PSG, however, sees him as the heir to Thiago Silva, whose form this season suggests it is in decline.
The problem now is, however, that Ajax has no financial obligation to sell.
De Jong's mega money transfer to Barcelona will keep the finances close at hand.
And Ajax still has a lot of money in the bank from Justin Kluivert's departure, who joined Rome in the summer.
Where De Jong's Barcelona move is bad for United and PSG, however, it's good news for Tottenham.
And this because of the interest of Spurs for Adrien Rabiot.
France Football has declared that Tottenham is trying to sign the French national team, despite Barcelona appearing in pole position to bring him to the ground.
De Jong's move to the Nou Camp could, however, see the revaluation of Barcelona.
The Ajax midfielder will have to fight with Sergio Busquets, Ivan Rakitic, Arthur Melo and Philippe Coutinho for a central position.