The 36-year-old announced his retirement from the NFL on Saturday via a statement posted on Facebook, citing a desire to be closer to his family that outweighed his current passion for the game.
Harrison earned a reputation as one of the fiercest linebackers in the league over ten years with the Pittsburgh Steelers from 2002-12 and won Defensive Player of the Year honors in 2008.
After the Steelers released him in March 2013, Harrison signed with the Cincinnati Bengals, where he recorded two sacks and one interception in 15 games played during the 2013 season. The Bengals released Harrison in March.