The Germany defender has agreed a three-year extension to his previous deal and declared it an "honour" to have committed his future to the Bundesliga club.
"Bayern are one of the great clubs in world football," the 25-year-old told the club's official website. "To play here is not only a job, it is an honour.
"I want to achieve a lot with our team in the years to come."
Bayern chief executive officer Karl-Heinz Rummenigge also revealed his delight at the news, citing Boateng as a key player for Pep Guardiola's team.
"He is one of the major players at Bayern," Rummenigge said. "For this reason it was a natural fit that we have endeavoured to ensure a contract extension."
Boateng moved to the Allianz Arena in July 2011 after a low-key spell with Manchester City, where he made just 19 appearances in all competitions.
He was part of the Bayern side that won the Bundesliga, UEFA Champions League and DFB-Pokal treble last season.
