The defender moves to the Catalan giants from their fellow LaLiga side, Barca having triggered his release clause
The Frenchman has signed a five-year contract at Camp Nou, with Barca having paid his €35 million (£31m/$41m) release clause.
Lenglet's deal includes a release clause, which stands at €300m (£264m/$350m), and runs until June 30 2023
Lenglet became one of Europe's most sought-after defenders at Sevilla, following his arrival from Ligue 1 side Nancy in January 2017.

Manchester United were also credited with an interest in securing his signature, but Lenglet has opted to stay in La Liga with Barca.

The 23-year-old joins a growing French contingent at Camp Nou, including forward Ousmane Dembele, and defenders Lucas Digne and Samuel Umtiti.
Lenglet enjoyed a productive spell at Sevilla, making over 70 appearances and scoring four goals for the club.
He is yet to be capped by France at senior level, but has won 10 caps at Under-21 level. He has, however, been capped at every level between U16 and U21.
Lenglet becomes Barcelona's second major signing of the summer, after Arthur arrived from Gremio for €40m on Monday.

www.goal.com/en/news/barcelona-sign-35m-lenglet-from-sevilla/1j2q23s07t92j14aacc7fljq4i