The Poland international wants to add more silverware to his trophy cabinet at BVB before moving on, but realizes the club will have to improve.
BVB currently trails Bayern by 17 points in the Bundesliga table and is unlikely to dethrone the reigning champion this term.
However, Dortmund still has every chance of winning a major trophy as the club has reached the Champions League round of 16, where it will meet Zenit St Petersburg, and the DFB Pokal quarterfinals, in which Eintract Frankfurt awaits.
"My goal remains to leave Borussia Dortmund with a trophy this summer," Lewandowski was quoted as saying by Sport Bild. "But we all know we have to improve. Of course, we had a lot of injured players, but we all saw that we have to give our all as a team in every game.
"A lot of people have claimed that I am no longer interested in playing for Dortmund, but I have shown that I am still keen to play for BVB. I want to give the fans a nice farewell gift."
Lewandowski has netted 11 goals in 19 Bundesliga appearances so far this term, but has yet to score since announcing his move to Bayern.