The club relayed the news on Friday on their official Twitter account:
In a statement on the club's official website, it's noted the Italian champions will pay €9.5 million (£8 million) for the Uruguayan midfielder over the next two seasons.
"The purchase value may increase in the course of the duration of the contract on achieving given conditions based on a certain number of official games played by the player," the report continued. "Moreover, in case of a later transfer of the player, Boca Juniors will be entitled to receive 50 per cent of the amounts collected by Juventus."
Bentancur arrives at Juventus having established a reputation as one of the most exciting young players in South America. Here's what the 19-year-old can offer:
The midfielder made his senior debut for the Buenos Aires giants in 2015 and went on to establish himself as an important member of the first team. He made 17 appearances in the 2016-17 Primera Division campaign for the Argentinian side.
When Juventus sold Carlos Tevez to Boca in 2015, they were able to secure a first option on the youngster, and he'll join up with the Italian champions ahead of the 2017-18 term.
Bleacher Report's Gianni Verschueren is excited to see what the teenager will be able to bring to the Bianconeri setup:
As noted by the Juventus website, Bentancur is a versatile young footballer who has operated in various midfield berths for Boca. His ability to thrive from deep and in a more advanced position will give manager Massimiliano Allegri even more variety in the middle of the park.
But it may be a while until he establishes himself in the starting XI. The club are stocked in midfield with Miralem Pjanic, Sami Khedira, Claudio Marchisio and Mario Lemina, and there's plenty of young talent, too. Rolando Mandragora is one of Italy's top prospects, and Grigoris Kastanos was a Primavera standout before joining Pescara on loan.
For more news, rumours and related stories about Bentancur, Juventus and Serie A, check out the Serie A and Juventus streams on Bleacher Report's app.