The team announced the addition Tuesday. Moats was waived by the Houston Texans last week after rushing for 390 yards and four touchdowns last season.
Vikings coach Brad Childress was the offensive coordinator in Philadelphia in 2005, when Moats was a rookie. The Eagles drafted him in the third round out of Louisiana Tech.
Moats signed with the Texans in 2008 and filled in at times for starter Steve Slaton in 2009. He had a career game at Buffalo on Nov. 1, with 126 yards and three touchdowns.