Johnson has started 61 games over the past four seasons, including at left guard in 2014. He first signed with the team in August 2011 and re-signed on a reported two-year, $5 million deal in March 2014.
Johnson, 30, spent the first five seasons of his career with the Indianapolis Colts. The move will save the Vikings $2.5 million in salary cap space. Johnson is now eligible to sign with any team as an unrestricted free agent.