Mancini aims to copy United
United have responded to their narrow loss in the battle for the Barclays Premier League crown last year by dominating the current campaign.
Sir Alex Ferguson's United men almost have both hands on the trophy as they head into tonight's derby against City at Old Trafford with a 15-point lead over their neighbors at the top.
City manager Mancini now wants to make sure the Eastlands club make the right moves over the summer to ensure it is his team that once again lead the way next term.
The Italian said: "Last year United didn't win anything - Community Shield, yes - but they continue to improve their team.
"This can happen, you can't win every year. This is impossible in England.
"For this, I think we need to do better next year."
Mancini failed to land all his prime transfer targets last summer, but with new administration at the club he is confident of doing better this time around.
City did strike one important blow last week when the inspirational Yaya Toure, after speculation he could leave, signed a new four-year contract and spoke of his confidence in the club's future.
Mancini said: "This is important for the club, it is important that they sign new contracts.
"We know that we should buy important players for next year if we want to improve.
"In football you can buy good players and afterwards you don't win - this is football, it is incredible.
"But I am sure we can do well this year, we can do a good job in the market."
Ferguson's success over the past two decades has owed much to his ability to continually refresh his side.
Having only emerged from a 35-year run without a major trophy in 2011, City are still to get to grips with this process.
Mancini said: "I think we need to improve as a team, as a club, but for this we need more years.
"We can't do this in two years. For 10 years, if we improve, if we win every year, probably it will be the same also for us."
Mancini is likely to want to strengthen his squad in a number of areas but is giving little away as to his intentions now.
He said: "I don't know, it is difficult to say this.
"You may want one player, but maybe two or three teams want the same player and after you can take this or take another player. It is difficult."
The title race may be all but over, but City still want to make a point tonight to prove the gap between them and United is not as large as the table suggests.
Mancini said: "I think we know we can beat them because they are not better than us.
"This is sure, 100 per cent - although they deserve to win this title."