Sarri, 60, joins the Seria A champions after spending just one season at Chelsea, where he guided the team to third in the Premier League as well as winning the Europa League title.
Juve have reportedly agreed a compensation fee of around £5 million ($6.2 million) with Chelsea, as Sarri called time on what was a tepid relationship with fans at the club.
In announcing the move, Juventus detailed Sarri’s experience with Seria A clubs Empoli and Napoli, adding that “now the adventure begins for him in Turin: welcome to Juventus!”
Chelsea also issued a short message on social media, thanking Sarri and wishing him well for the future.
Sarri inherits a Juve team from former manager Max Allegri containing the considerable talents of Portuguese star Cristiano Ronaldo, and which sealed an eighth straight Seria A title by a huge margin last season.
His task will stretch far beyond domestic glory, however, as he will be charged with ending the club’s two-decade wait for success in the Champions League.
Chelsea, meanwhile, are stepping up their search for Sarri’s replacement, with club legend Frank Lampard said to be the favored appointment.