The Panthers released Johnson on Monday, Bryan Strickland of the Panthers' official site reports.
With Carolina in need of cap space and Johnson coming off a season in which he failed to record a sack in 12 games while missing four contests for violating the NFL's performance-enhancing drugs policy, the 31-year-old was always considered a prime candidate to get cut before the start of the new league year. Given his lack of productivity as a pass rusher in recent seasons, Johnson, who ranks second in franchise history with 67.5 sacks, could have difficulty landing anything more than a one-year deal in free agency this offseason.