The Argentinian will also be joined by Carles Puyol and Xavi in committing themselves to the club for the foreseeable future. Messi's new deal will run to 2018, while Xavi and Puyol will both sign until 2016.
"In the coming weeks Puyol, Xavi and Messi will sign their respective new contracts," the club said in a statement. "This news means that FC Barcelona has secured its ties with three of its most important players."
Lionel Messi has just come off the back of a remarkable year in which he broke Gerd Muller's 40-year record of scoring more than 85 goals in a calendar year. He has been playing in the club's first team since 2004, the year that Carles Puyol became captain.
Xavi, meanwhile, holds the record for the most appearances for the club of all time, currently standing at 651. For he and Puyol, it's concievable that they could be the last contracts the veteran duo sign. How Barcelona would move on from that will be fascinating - but won't need to be thought about for a while yet.