Juventus shared pictures and a video of Weah's arrival at the Turin airport this evening on both their website and social media.
Weah, who joined Lille from Paris St Germain in June 2019, will undergo his medical on Thursday, Italian media reported, before signing a deal reported to be worth 12 million euros ($13.10 million) for five seasons.
While he has operated as a defender for Lille, Weah has predominantly played as a winger in his 31 matches for the United States since his debut in 2018.
Weah is the son of former AC Milan and Paris St Germain striker George Weah, who won the World Footballer of the Year and the Ballon d'Or awards in 1995 and is the current Liberia President.
Timothy Weah was born in New York and was eligible to represent France, Jamaica, and Liberia, but he ultimately chose to represent the United States.
He was part of the squad that reached the last 16 at the 2022 World Cup in Qatar.