It will be the first time since 2012 that the 66-year-old, Germany's greatest-ever golfer, will play at the prestigious event, which runs from July 3-7.
The two-time Masters champion, who's been the star of the US Seniors Tour for a long period and won the US Senior Open this year, lifted 42 titles in all on the main European tour.
"I'm really looking forward to the 35th BMW International Open, which has a special significance for me. I took part in the first event in 1989 and only missed it twice before the 25th anniversary," Langer said in a statement on Thursday.
"Even though I've been competing on the PGA Tour Champions in the US for years, I can't think of a more atmospheric tournament to say goodbye to the DP World Tour than the BMW International Open."
The six-time Ryder Cup winner - five times as a player, once as the European captain - has enjoyed a glittering career but has never won the BMW International Open in his home of Bavaria.
But Langer does hold one record, having finished runner-up on no fewer than five occasions (1992, 1995, 2000, 2002, 2007) in his 23 appearances.
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