Ronaldo joined United for a second time at the start of the season from Juventus and has made 27 appearances so far, scoring 15 goals.
The 37-year-old’s form has been indifferent and he recently went on a six-game goal drought before ending the barren spell with a strike against Brighton and Hove Albion on Tuesday.
There have been rumours of a power struggle between Ronaldo and Harry Maguire regarding the Manchester United captaincy but those suggestions have been refuted by interim manager Ralph Rangnick.
Carragher believes the media focus on Ronaldo is hindering Manchester United’s progress and he should be moved on at the end of the season.
"Cristiano Ronaldo’s invaluable contribution to Manchester United’s Premier League win over Brighton was another reminder of his unparalleled appetite for goals,” Carragher wrote in the Telegraph.
"But it does not change this reality: United made a mistake re-signing Ronaldo last summer. It will be a bigger one keeping him next season.
"Whether United wins, loses or Ronaldo scores or goes through a mini goal-drought, it is still too much about the CR7 brand and not enough about the team. After United’s midweek win, Ronaldo posted on social media about ‘the noise’ around the club. He cannot ignore where a lot of that noise comes from."