After a 1-1 draw against Bayern Munich in the first leg, United's European dreams are still alive ahead of tomorrow's crucial clash.
Rooney said: "Of course (I believe we can win it).
"When Chelsea won it they nearly went out of the competition three times.
"We believe we can go through. We have good enough players.
"It will be tough because in my opinion Bayern and Barcelona are the two best teams left in the competition, so we have to be at our best.
"We are ready. It's an exciting game for us all - the players and the fans - and it's a massive game to be involved in."