Westbrook spent eight seasons in Philadelphia, finishing his career with the Eagles in 2009 as the franchise leader with 9,875 total yards from scrimmage.
"I will always remember Brian for the electrifying, game-changing plays he made during his great career in Philadelphia," Eagles owner Jeffrey Lurie said. "He was one of those players you knew could score from anywhere on the field and one of the most exciting players I have ever watched."
The Eagles will honor Westbrook at Lincoln Financial Field on Dec. 23 during halftime against the Washington Redskins.
Known for his speed and pass-catching ability, Westbrook is one of six players in league history to amass 30-plus rushing (41) and receiving (30) touchdowns in his career. The two-time Pro Bowler last played with the San Francisco 49ers during the 2010 season.
Westbrook, a second-round pick out of Villanova, enjoyed his best season in 2007, when he led the NFL with 2,104 yards from scrimmage.