Barcelona have agreed a 20 million euro fee to sign Jeremy Mathieu from Valencia.
Mathieu, 30, will sign a four-year contract at the Camp Nou, with the option of a further year.
"I'm very proud to come to Barcelona," he said, according to AS.com. "I've come to bring quality to the team. Barca is the best club in the world, and coming here is a great opportunity for me."
The Frenchman arrived at Valencia from Toulouse in 2009 and went on to make 94 Liga appearances for Los Che.
Mathieu, who can play in defence and midfield, started 48 games for Valencia in all competitions last season, scoring four goals.
Valencia said in a statement on their official website: "Valencia CF thanks Mathieu for his professionalism and performances over the five years he has played for our club."