The Argentinian has signed a contract with the Bianconeri until 2024 and will return to Genoa on loan for one more season.
News of the deal did not come as a surprise, as the 21-year-old defender had his medical earlier this week:
Romero is the second central defender to join the Italian champions this summer, with Merih Demiral making the switch from Sassuolo.
A third is reportedly on the way as well, with Ajax's Matthijs de Ligt expected to land in Turin soon, per sportswriter Fabrizio Romano.
Juventus were in need of a youth movement in defence. Andrea Barzagli retired at the end of last season, and Giorgio Chiellini is 34 years old and likely won't be around for much longer, either.
With Demiral and De Jong expected to be part of the squad next season, the Bianconeri have opted to leave Romero in Genoa for one more year, where he'll see more playing time and have the chance to develop quickly.
Sportswriter Matteo Bonetti is excited for the future of Juventus' defence:
Romero started 27 Serie A matches last season, his first in Italy. He stood out for his aggressive, physical play, and will have to work on his patience and temper moving forward. With 10 yellow cards and two sending-offs, his disciplinary record left a lot to be desired last season.