Winning the Europa League would give them precious co-efficient points needed to avoid another tough draw in next season's Champions League.
Mancini said: "We want to qualify for the Europa League if we can. It will help to keep all the players in the squad happy because they will play more.
"It is an important competition if you win it. It helps in the Champions League and you get to play in the Super Cup in Monaco.
"But if you are in it you have to win it. If you play a lot of games but don't win the trophy, you get the kind of problems with tiredness that we had last season.
"So on one hand it is good to be in it and on the other it isn't. If we qualify then we will try to win it."