The team made the announcement in a news release issued Tuesday morning.
"I had a chance to speak with him today and he handled himself like the true professional he is," head coach Chip Kelly was quoted as saying in the release.
The team notes that Avant, who played eight season with the Eagles, ranks 11th in team history with 297 receptions for 3,646 yards and 12 touchdowns.
Avant was drafted in the 4th round in 2006 from the University of Michigan.
General manager Howie Roseman was quoted as saying "There's no question that releasing a player like Jason is one of the toughest parts of the job. It's a tough day when you have to say goodbye to player who you have so much respect for. I can't thank him enough for the leadership, the big plays and the positive impression he made on so many of his teammates."
"There have not been any players who have represented the Philadelphia Eagles with more class and dignity than Jason Avant," said Eagles Chairman Jeffrey Lurie in the statement. "Whether it was in the locker room, on the playing field or in the community, he has always been a true professional, a role model and a winner every step of the way. On behalf of the entire organization, I wish Jason and his wife Stacy, and their two daughters, nothing but the best as he continues his fine career."
The Eagles released Avant less than one week after re-signing wide receiver Riley Cooper to a five-year, $25 million deal and bringing back receiver Jeremy Maclin on a one-year deal worth up to $6 million.