Barcelona have completed a EUR40million deal to sign Paulinho from Guangzhou Evergrande Taobao.
The Brazil international finalised his move to Camp Nou after completing a medical and agreeing terms on a reported four-year contract on Thursday.
Paulinho completing his switch has been a formality ever since a deal was announced by Barca on Monday, ending an on-off transfer saga in which Guangzhou attempted to hold on to their prized asset.
The 29-year-old is Ernesto Valverde's first signing since the world-record EUR222m sale of Neymar to Paris Saint-Germain.
Barca have not confirmed the length of Paulinho's contract, but previously stated that it will include a EUR120m buy-out clause.
It comes after weeks of speculation over his future and marks an impressive revival in Paulinho's career.
Having struggled to convince at Tottenham following a move from Corinthians in 2013, he left to join Guangzhou two years later to link up with former Brazil boss Luiz Felipe Scolari.
Paulinho helped the club to win six trophies, including two league titles and the AFC Champions League, and his performances earned him a recall to the national team.
The departed Neymar was among the stars to wish Paulinho well after the deal was agreed.
On Wednesday, Barcelona threatened to take legal action as they strongly denied media allegations that a company owned by club president Josep Maria Bartomeu will benefit from the midfielder's move.
Barcelona, whose season on the pitch got off to a rocky start with a 5-1 Supercopa de Espana defeat to rivals Real Madrid, are also chasing Philippe Coutinho and Ousmane Dembele.