Carlo Ancelotti's side secured it in emphatic style with a 6-0 win over Wolfsburg, with David Alaba, Robert Lewandowski (two), Thomas Muller, Joshua Kimmich and Arjen Robben scoring.
It represents what will be the final piece of silverware in Lahm's glittering career, with the 33-year-old FIFA World Cup winner set to retire at the end of the season.
Lahm has won 21 trophies with Bayern - including eight Bundesliga titles and one UEFA Champions League triumph - but he revealed his disappointment in not having found the net on more occasions.
"Eight leagues, 21 titles, yeah ok, that's great. But not many goals? That could have been better!" Lahm said.
"Winning the Bundesliga is never a given. I have to enjoy the last few weeks now, every training session.
"On the final day, I will take everything in. Many people will be in the stadium, my family, friends.
"There were many highlights. The first German championship, for example. Even if I won so many titles, the first title is not forgotten.
"But the really special thing about all these years was the co-operation with the players, coaches, mentors."
Despite his decision to retire, Lahm has remained a regular for Bayern throughout the season, but the defender insists he has no doubt about ending his playing days.
"I can feel it. I just have that feeling. In training and in games. It will be the right decision," Lahm continued.