The Old Lady have chosen former Italian national team head coach Spalletti to take the helm for the remainder of the campaign.
The experienced coach steps in for the Croatian manager, who was sacked after the Serie A side's defeat by Lazio recently.
Tudor had joined the club in March to replace Thiago Motta but departed after seven months after an eight-game winless streak.
Spalletti led Napoli to the Serie A title in 2022-23 prior to assuming the Italy role, who had failed to qualify for the 2022 World Cup during Roberto Mancini's tenure.
He helped them qualify for Euro 2024 where they were knocked out in the last 16 by Switzerland.
However, Spalletti was sacked by Italy in June post a qualifying defeat against Norway, as Italy faced the possibility of not making a third World Cup in a row.
Spalletti's managerial career includes Inter Milan, Roma, and Udinese in Serie A and lifted the Russian league trophy twice while at Zenit St Petersburg.
Juventus were temporarily led by Massimo Brambilla in the midweek 3-1 triumph over Udinese which left them seventh in Serie A - six points adrift of Napoli at the top after nine rounds.
Their Champions League campaign sees them in 25th place in the group stage, after recording one defeat and two ties in the initial three fixtures.
