The star linebacker told the team "This will be my last ride." He has been out since Oct. 14 with a triceps injury, but expects to play Sunday in the wild-card round against Indianapolis.
The 37-year-old Lewis says "It is time for me to create a new legacy" after 17 NFL seasons.
Lewis was the AP Defensive Player of the Year in 2000, when Baltimore won the Super Bowl title, and in 2003.