"After 11 years of having played the greatest team sport at its highest level, it's now time for me to announce my retirement from the NFL," the 34-year-old Harris said in a statement.
Harris was a second-round draft pick of the New York Jets in 2007 out of the University of Michigan. He spent 10 years with the Jets and was named a second-team All-Pro after the 2009 season.
After being released by the Jets, Harris played 10 games and made six starts for the Patriots last season, when he had 1.5 sacks. However, he did not play after Week 15 of the regular season.