The 17-year-old winger, whose full name is Paulo Henrique Sampaio Filho, will move from Rio de Janeiro side Vasco da Gama on the day of his 18th birthday in July on a five-year deal.
German media reports say Leverkusen will pay up to 20 million euros for his signature ($24.2 million).
“The signing of Paulinho is a huge success for us,” said the club’s CEO Michael Schade.
Leverkusen currently sit fourth in the Bundesliga with three games remaining, meaning they are on course for a return to the Champions League next season.
Paulinho’s decision to move to the Werkself may seem surprising, but the 2002 Champions League runners-up have a history of bringing through South American talents — Brazilians Lucio and Ze Roberto are notable former players, as is Chile midfielder Arturo Vidal.
“The club has a great reputation back home and everybody knows them as a club in Europe where a lot of Brazilians have been happy,” Paulinho said in a statement on Leverkusen’s website.
“I think it’s important to fully consider a move abroad, that’s why I’ve chosen a club that works seriously and yet still pursues great ambitions.”
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