Lewandowski has scored 16 goals in 11 club appearances so far this term, as well as a further six for Poland in their Euro 2016 qualifying campaign.
And Wenger believes his defenders will have to be at the top of their game to get the better of him.
"First of all the best way to combat him is for us to have the ball," Wenger was quoted as saying by Arsenal's official website.
"After that you have to be shrewd with him because inside the box he is outstanding, because of his technique, his finishing, his movement inside the box.
"That’s where we need the experience of Mertesacker and Koscielny to deal with that because that will be one of the important things on the night."
Bayern are among the favourites to win the Champions League this season, with Pep Guardiola's outfit top of Group F after wins over Olympiacos and Dinamo Zagreb.
The Bavarians have also triumphed in all nine of their Bundesliga encounters to date, and Wenger believes Arsenal are underdogs ahead of Tuesday's clash at the Emirates Stadium.
"You have to respect Bayern," he said. "Historically they have won the European Cup how many times? Five? And Arsenal zero. So you cannot say that historically we are at the same level as Bayern.
"They have done it in the past and they have the history and the knowledge. What we want is to get there.
"In 2015 we are the team that has taken more points than everybody else. But in Europe it’s true we have been poor in our first two games. That is what we want to correct.
"I must say we have our backs to the wall and we play against a top, top team. So I can understand the scepticism of people. But we have to prove them wrong.
"We don’t look at the history. We look at the potential performance on the day. That’s what we try to do. The history doesn’t play the game. What will decide the game is the performance we produce. That comes from if we believe we can do it."