The Poland international joined the German champions on a free transfer from Borussia Dortmund in July, with his arrival prompting the departure of Mario Mandzukic to Atletico Madrid.
Lahm does not think that the latter, who served Bayern well, will be missed, as he feels that Lewandowski will prove an instant hit at the Allianz Arena.
"Robert is currently one of the best strikers in the world, if not the best," the versatile defender told Munchner Merkur.
"He's more than an adequate replacement for Mario Mandzukic. I think he will settle quickly with us. We have a top squad with no weak points in terms of quality."
Lewandowski is due to make his competitive debut against his old club in the DFL-Supercup on Wednesday and Lahm is keen to win even more silverware after two years of success with both club and country.
"I'm absolutely addicted to winning and I'm motivated to repeat this success," Germany's World Cup-winning captain stated. "Victory is the goal.
"If we play as well as we did last year [in the Bundesliga] then I'm sure we'll be champions again."
Lahm announced his retirement from international football after leading Germany to glory at Brazil 2014 this summer.