The ex-Spain international, who spent eight seasons in Catalunya as a player and a further three in charge of the club's B team, will succeed Tata Martino at the helm.
Barcelona have confirmed the appointment of Luis Enrique as their new coach on a two-year contract.
The ex-Spain international, who spent eight seasons at Camp Nou as a player and another three in charge of the club's B team, takes over from Gerardo Martino, who stepped down after the Blaugrana were dethroned as Liga champions following a 1-1 draw at home to Atletico Madrid on Saturday.
Luis Enrique met Barca sporting director Andoni Zubizarreta at his home in Gava earlier this month and his move was a formality as soon as he stepped down as Celta boss on Friday.
"The FC Barcelona Board of Directors have this evening confirmed Luis Enrique Martinez as the new first team coach, following a proposal from sporting director Andoni Zubizarreta," a short statement read on Monday.
"Luis Enrique, 44, will sign a two-year deal."
The former midfield ace joined Barca from great rivals Real Madrid in 1996 and went on to establish himself as a firm favourite with the Camp Nou crowd, winning two Liga titles, two Copas del Rey and a Uefa Cup Winners' Cup before retiring in 2004.
Luis Enrique rejoined the club as a coach just four years later and enjoyed a successful stint in charge of their B team before departing for Roma in 2011.
He only stayed at the Stadio Olimpico for a solitary season before returning to the game in 2013 to take charge at Celta, whom he led to a ninth-placed finish in La Liga.