The former United States coach joined the Galaxy in 2008 and has since led the Californian outfit to three MLS Cup finals, claiming the title in both 2011 and 2012.
He has also achieved first-place finishes in the Western Conference in three of the last five seasons, winning the Supporters' Shield in 2010 and 2011.
"We are very pleased to sign Bruce Arena to a multi-year contract extension," said Dan Beckerman, president and CEO of AEG, the company that owns the Galaxy.
"Bruce is one of the finest coaches in the history of soccer in the United States.
"His commitment to the LA Galaxy, the club’s winning tradition and continued excellence on and off the field is unrivaled.
"We look forward to the team's continued success under Bruce's management."
Arena is the first coach to win four MLS Cup titles, and declared his pride at continuing in his role.
"I'm honored to remain in this role with the pre-eminent soccer club in the United States," he said. "I appreciate the continued support and confidence from ... my staff and players as we head into the 2014 season."
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