The Poland international, who will be joining Bayern Munich at the end of the season, scored four times in last year's semi-final first leg against the Spaniards in a memorable performance.
This time, however, Real have arrived with a 3-0 advantage from the first leg in Madrid and are the favourites to book a spot in the semi-finals.
"If you think that I will score four goals just like last season then that is crazy. But we still remain dangerous, especially at home," he told reporters.
"We are different team than last year. But we still have good players and great potential. We do have a lot of injuries and Real are in top form."
Lewandowski had missed the first leg in Spain through suspension and a lot is resting on his shoulders as last season's runners-up attempt a major comeback against the nine-times European champions.
"I was a bit sad not to play in Madrid but I still believe that we have a slim chance. We have to be aggressive," said Lewandowski ahead of what could be his final European home game after four seasons at Dortmund.
Dortmund will also be without suspended captain Sebastian Kehl.
Their 2-1 win over VfL Wolfsburg on Saturday with a superb second half performance eased some of the domestic pressure as they tightened their hold on second place with five league matches left in the campaign.
"As we seem to be specialists in second halves at the moment, tomorrow is the second half of our quarter-final," Dortmund coach Juergen Klopp told reporters.
He said keeper Roman Weidenfeller could be back fit after missing on Saturday while midfielder Nuri Sahin is still nursing a minor back injury and a decision on his participation will be taken on Tuesday.
"We have no right to be dreaming of a miracle," Klopp said. "What we have to do is give it everything we have. The first thing is to defend better than in the first leg and the second thing is to use our goal chances better.
"Even if we are eliminated we want to do it with a superb performance."
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