He signed a four-year contract with a buyout clause of EUR400 million.
Juve's Miralem Pjanic will also move in the other direction, although both players will conclude the 2019-20 campaign at their current clubs.
The 30-year-old Bosnian will move to the Camp Nou on a four-year deal after the ongoing season is completed. The purchase value may increase of maximum 10 million euros on achieving given conditions during the course of the contract.
Back in 2018, Arthur joined Barca from Brazilian club Gremio and was hailed as the club's future star.
'He is a player until the last game of the season.
It has been understood that Barcelona has been hit hard because of the three-month suspension due to the novel coronavirus pandemic. The board can generate some immediate profit through Arthur's sale.
The Bosnia and Herzegovina worldwide joined Juventus from Roma in 2016, helping the Bianconeri win the Italian Serie A title three times. He was brought up in Luxembourg and initially made his name in French football with Metz and then Lyon.
"FC Barcelona and Juventus FC have reached an agreement for the transfer of player Arthur Melo".
Juve confirmed they will pay a fee of €72 million (R1.4 billion) plus €10 million (R194 million) in add-ons for the 23-year-old, while they will receive €60 million (R1.2 billion) plus another €5 million (R97 million) in performance-based bonuses from Barcelona for Pjanic.
Setien said in a press conference on Monday the playmaker had promised to give his all for the rest of the season as Barcelona look to make up a two-point gap on Real Madrid at the top of the table.