The Italian admits he doesn't know whether the Argentinian will stay or not, but for the time being his side's attention will be on the clash against Stoke in the FA Cup final
Tevez handed in a transfer request earlier on in the season but later withdrew it and subsequently speculation has surrounded the talismanic player since.
Mancini insists that his sought after striker should leave the club if he is unhappy.
"If I'm not happy to stay, then I'll leave. It's the same for the players. If they aren't happy to stay, it's better they leave," Mancini told reporters.
"When you start your job you should be happy, because the season is long and there could be a thousand problems.
"Carlos has got a five-year contract, but in my opinion a player should stay here because he believes in the project and he's happy to stay at the club.
"I have never said that Carlos wants to leave - I said that it would be his decision. At the moment, he has a five-year contract here.
"He's scored 22 goals and that's very important. But we've got this far because all the players have contributed.
"I would say all the players here at the moment are happy to stay because this season they've worked well together and we've got into the Champions League."
The 26-year-old had an altercation with his manager during the game at Tottenham as Mancini kept Tevez - eager to come on as a substitute – waiting on the sidelines.
Asked whether the Argentinian will be at Eastlands next year, Manini replied: "I don't know. "We have a good team this year but we need to improve.
"To win the title is harder but if we can buy good players with experience of winning with other teams, that would be good for everyone."
Mancini’s side face Stoke in the FA Cup final on Saturday, and the Italian is weary that his side hasn't beaten them in their previous four encounters.
"We've played against Stoke four times in the past year and we've had a problem in every game," he added. "They are not easy to play against.
"We have to focus on every situation. Their set-pieces could be difficult for us. We must be patient and work hard.
"Stoke are different from any other team.
"They are a physical team and the game will be 95 minutes, maybe more if there's extra-time."