A loan deal worth €4 million is on the cards, and La Viola will have a purchase option of €20m for the Brazilian midfielder.
Arthur, whose contract expires in 2025, is expected to pen a new deal with the Bianconeri before leaving on loan.
The Brazilian midfielder has endured a steep decline since completing his move from Barcelona to Turin in a controversial swap deal involving Miralem Pjanic.
The deal has been cited as one of the most expensive flops in recent memory, as neither player has had a successful time since switching clubs.
Arthur went from one of the most highly-coveted midfielders in the world to a fringe figure at Juventus.
The former Gremio star also spent a disastrous loan spell at Liverpool last season, being restricted to just a single appearance in the Champions League in an injury-plagued campaign.
With Juve manager Massimiliano Allegri not counting on the midfielder for the upcoming season, Arthur will be eager to make his mark elsewhere.
There will be no better place than Fiorentina to do so, with master tactician Vincenzo Italiano capable of reigniting his career.
Juve could also lose Paul Pogba, who continues to attract interest from Saudi Pro League clubs.
It could prompt the Bianconeri to explore the market for midfield reinforcements, with Barcelona’s Franck Kessie one of the top targets.