"The 23-year-old completed his switch from the Italian side and has joined the club on a five-year contract," Southampton said in a statement posted on their website on Tuesday.
Confirming Lemina's sale, Juventus said that Southampton's cost may increase up to maximum 20 million euros ($23.47 million) on achieving given sport conditions in the course of the duration of the contract.
A senior international with Gabon, Lemina started his career in France, with Lorient, before joining Marseille in 2013 and then moving to Juventus in 2015, initially on loan, before completing a permanent transfer last summer.
In his time with the Bianconeri, he won both the Serie A title and the Coppa Italia twice, and featured in last season's Champions League final, against Real Madrid.
Southmapton Vice Chairman (Football) Les Reed said in the statement: "Mario is an outstanding talent who has already achieved a great deal in his career, winning a number of titles and gaining experience of playing on some of the biggest stages in world football.
"Investing in a player of Mario's quality and buying from a club like Juventus is a significant statement of intent from the club, and this is a purchase that has set another club-record fee.
"In a volatile market with some extraordinary and inexplicable transfers taking place, we are determined to go about our work in a diligent and correct way.
"This is a player who has won trophies and played in the Champions League final less than three months ago and he has signed for Saints amid a host of suitors."
Commenting on his move, Lemina said: "I am really happy to have signed for Southampton. I think that it was the project that attracted me the most and the one my family was really behind. I am really happy to be here."
Turin giants Juventus said that they will get a profit of 9.4 million euros ($11.03 million) from Lemina's sale.
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
About VDC
Doraiah Chowdary Vundavally is a Software engineer at VTech . He is the news editor of SocialNews.XYZ and Freelance writer-contributes Telugu and English Columns on Films, Politics, and Gossips. He is the primary contributor for South Cinema Section of SocialNews.XYZ. His mission is to help to develop SocialNews.XYZ into a News website that has no bias or judgement towards any.